I. Introduction

Inquiry-Based Learning (IBL) is a student-centered instructional approach that emphasizes active learning through questioning, exploration, investigation, and knowledge construction based on students’ direct experiences [1].In educational settings, Inquiry-Based Learning (IBL) is commonly carried out through a series of systematic phases, namely questioning, investigating, creating, discussing, and reflecting. During these phases, students take an active role in learning by generating questions, seeking and analyzing information collaboratively, developing their understanding, and sharing their findings with others. This learner-centered approach transforms the teacher’s role from being the primary source of knowledge into a facilitator who supports, guides, and monitors students throughout the inquiry process [2].

In the context of English language teaching, particularly in developing speaking skills, IBL provides meaningful opportunities for students to use English communicatively through interactive and inquiry-driven activities [3]. Speaking instruction through Inquiry-Based Learning (IBL) extends beyond simply responding to questions. It involves a structured learning process in which students investigate topics, develop and express their ideas, and participate in discussions or presentations. Consequently, the successful implementation of IBL in speaking classrooms depends on careful instructional design to ensure that each stage of the inquiry process contributes effectively to the improvement of students’ oral communication abilities

In this study, the planning of IBL implementation in speaking classes is designed based on five main stages. First, in the questioning stage, the teacher introduces a topic and stimulates students’ curiosity through guiding questions related to real-life contexts. Second, in the investigating stage, students work collaboratively in small groups to explore vocabulary, expressions, and relevant information needed for speaking tasks. Third, in the creating stage, students construct their own spoken texts, such as describing themselves, others, or daily activities. Fourth, in the presenting stage, students perform their speaking tasks through presentations, dialogues, or group discussions. Finally, in the reflecting stage, both teacher and students evaluate the learning process, identify difficulties, and provide feedback to improve students’ speaking performance. Careful instructional planning ensures that Inquiry-Based Learning (IBL) can be effectively implemented in classroom practice rather than remaining merely a theoretical concept. Through well-designed learning activities [4] IBL provides meaningful opportunities for students to improve their speaking skills. Furthermore, this approach aligns closely with the principles of the Kurikulum Merdeka, which emphasizes student autonomy, active engagement, critical thinking, and contextualized learning. It also supports the development of communicative competence through various speaking activities, including discussions, presentations, and interactive communication.

The use of the English for Nusantara textbook further supports this approach, as it is designed based on the Kurikulum Merdeka framework and provides communicative tasks, inquiry-based activities, and contextually relevant materials suitable for junior high school students [5].Therefore, integrating Inquiry-Based Learning with English for Nusantara is expected to create meaningful learning experiences, improve students’ speaking abilities, and increase their confidence in using English for communication.

Within the Indonesian educational context, improving English speaking proficiency among junior high school students remains a significant concern. Many learners continue to experience difficulties in oral communication, including restricted vocabulary, low self-confidence, limited speaking ability, and feelings of anxiety when using English. These challenges are frequently linked to conventional teaching practices that emphasize grammatical accuracy and written tasks rather than communicative and interactive language use. Consequently, students are often provided with insufficient opportunities to practice speaking in authentic and meaningful situations, which may hinder the development of their communicative competence [6] [7].

To overcome these challenges, the English for Nusantara textbook offers a variety of inquiry-oriented activities designed to promote active student participation in the learning process [8]. The textbook incorporates inquiry-based tasks, collaborative learning experiences, and authentic communication situations that are appropriate to students’ language proficiency levels, making it well aligned with the principles of Inquiry-Based Learning (IBL) in English instruction. In addition, the active involvement of teachers, schools, and the broader educational community plays an essential role in fostering a supportive learning environment that motivates students to develop their speaking skills with greater confidence and meaningful communicative intent. Through collaborative efforts among educators, curriculum developers, and society in promoting innovative instructional approaches, the integration of Inquiry-Based Learning through English for Nusantara is expected to overcome existing learning barriers and strengthen students’ speaking competence in meeting the communicative demands of 21st-century education [9].

Although previous studies have shown that Inquiry-Based Learning can improve students’ speaking skills, most of these studies focus on general inquiry activities or use different instructional materials without specifically integrating the English for Nusantara textbook within the Kurikulum Merdeka context [10]. Furthermore, limited studies have provided a clear and structured explanation of how Inquiry-Based Learning is systematically implemented in speaking classrooms, particularly when integrated with the English for Nusantara textbook regarding how IBL is systematically planned and implemented in speaking classrooms. Therefore, this study aims to fill this gap by examining the effect of Inquiry-Based Learning on students’ speaking skills through a clearly structured implementation using the English for Nusantara textbook” [11].

Based on the results of classroom observations conducted in class VIIA at SMP Negeri 1 Wonoayu carried out in this study, it was found that many junior high school students still showed limited ability in using English for oral communication. A large proportion of students tended to avoid speaking, encountered difficulties in conveying their ideas verbally, and lacked confidence during speaking activities. These conditions suggest that students’ speaking skills had not yet developed optimally, which may be caused by the limited availability of active and meaningful speaking opportunities, as well as the frequent use of teacher-centered and less interactive instructional practices. Similar conditions have been reported in previous studies, indicating that the lack of communicative interaction in the classroom can hinder the development of students’ speaking skills at the secondary school level [12] [6]. Moreover, the development of speaking skills among junior high school students is influenced by various challenges, including low motivation to learn English such as difficulties in oral communication, anxiety when speaking in front of others, insufficient parental support, and the use of ineffective teaching strategies. Although interactive and collaborative learning approaches, such as Inquiry-Based Learning, supported by technology integration and adequate teacher preparation, have been shown to enhance students’ confidence and speaking competence, instructional practices in many classrooms still place limited emphasis on active oral communication. Therefore, the creation of a supportive and conducive learning environment, along with stronger collaboration between teachers, is essential to promote students’ active participation in speaking activities [13].

This research is based on several learning theories that are relevant to the application of Inquiry-Based Learning in enhancing students’ speaking skills. One of the primary theoretical foundations is Collaborative Learning Theory, which emphasizes the role of social interaction, peer cooperation, and collective knowledge construction in the learning process. Through collaborative inquiry-based activities, students are provided with opportunities to share ideas, negotiate meaning, and practice oral communication in a supportive learning environment, which can positively contribute to the development of their speaking skills [14]. Furthermore, this study is also supported by Problem-Based Learning (PBL) Theory [15] which highlights the use of real-life problems as a meaningful context for learning. In inquiry-oriented classrooms, students enhance their speaking skills through active participation in discussions, problem-solving activities, and oral presentations, which foster both communicative competence and critical thinking abilities [16]. These theoretical views provide a solid conceptual basis for explaining how Inquiry-Based Learning supports the development of students’ speaking competence through active, collaborative, and meaningful learning experiences.

Despite the strong theoretical support and positive findings from previous studies regarding the effectiveness of Inquiry-Based Learning and collaborative instructional approaches in improving students’ speaking skills, a gap remains between theoretical assumptions and classroom implementation. Prior studies, such as that conducted by C. Valentine [12] demonstrate that interactive techniques like Small Group Discussion can enhance students’ speaking performance; however, these studies focus on different instructional strategies and are conducted at different educational levels. Similarly, research by S. Nurhayati [14] confirms that Inquiry-Based Learning encourages students’ exploration and active communication, yet it does not sufficiently explain how specific components of speaking skills such as fluency, pronunciation, and coherence are developed, nor does it provide detailed information about classroom settings, instructional materials, and learning activities.

In reality, many English classrooms continue to apply teacher-centered teaching practices with limited opportunities for structured inquiry-based speaking activities, especially those integrated with officially recommended textbooks. The inconsistency between established theoretical frameworks and their practical application in classroom settings indicates the necessity for further investigation into the systematic use of Inquiry-Based Learning through the English for Nusantara textbook to improve junior high school students’ speaking skills. Grounded in the identified theoretical perspectives and research gaps, this study is intended to explore the influence of Inquiry-Based Learning on students’ speaking performance at the junior high school level using English for Nusantara. This study adopts a quantitative research design using a one-group pre-test and post-test approach to examine the improvement in students’ speaking performance after participating in Inquiry-Based Learning activities. The study highlights the application of inquiry-oriented instructional methods, collaborative learning experiences, and communicative language tasks presented in the English for Nusantara textbook, which are intended to support meaningful interaction and enhance students’ speaking competence effectively.

By providing empirical evidence on the effectiveness of this instructional approach, the study is expected to contribute to the enhancement of English language teaching practices and to support the effective implementation of the Merdeka Curriculum in Indonesian Junior High Schools.

Research Question

“Is there a significant difference in the speaking performance of junior high school students before and after the implementation of Inquiry-Based Learning using the English for Nusantara textbook?”

II. Method

Reserch Design

This study employed a pre-experiment quantitative research approach using a one-group pre-test and post-test design to examine the effect of Inquiry-Based Learning (IBL) on students’ speaking skills. This design involves a single group of participants who are tested before and after the implementation of the treatment. The purpose of this design is to measure the extent to which the treatment influences students’ performance by comparing the results obtained from the pre-test and post-test [10].

This study specifically focuses on the implementation of Inquiry-Based Learning using Chapter 1 “About Me” from the English for Nusantara textbook at the junior high school level. The design was chosen to evaluate students’ speaking performance prior to and following the implementation of the instructional treatment in order to determine any improvement attributable to the use of Inquiry-Based Learning [17].

Participants

The participants in this study consisted of 36 seventh-grade students from class 7A at SMP Negeri 1 Wonoayu. The selection of a single class was aligned with the research design, which employed a one-group pre-test and post-test approach. This design requires only one group to measure students’ speaking performance before and after the implementation of Inquiry-Based Learning (IBL).

The participants were selected using a purposive sampling technique. The class was chosen because it represented typical characteristics of junior high school students and had not previously been exposed to Inquiry-Based Learning in speaking instruction. Additionally, the class used English for Nusantara as the primary instructional material, which was relevant to the objectives of this study.

All students participated in the pre-test, treatment sessions, and post-test. The English teacher assisted in facilitating the implementation of Inquiry-Based Learning during the instructional process.

Research Instrument

In this study, the research instrument consisted of a speaking test administered as both a pre-test and post-test to evaluate students' speaking abilities before and after the implementation of Inquiry-Based Learning. The instrument consisted of an individual oral task that required students to share personal information through self-introductions and simple descriptive expressions, allowing their speaking abilities to be assessed in a communicative context.

The speaking tasks were adapted from Chapter 1 “About Me” in the English for Nusantara textbook, which focuses on self-introduction and basic interpersonal communication appropriate for seventh-grade students. The instrument was designed to align with the instructional objectives of the material, ensuring content validity. Students’ speaking performances were assessed using an analytic scoring rubric adapted from Brown [3].

which evaluates five components of speaking ability: pronunciation, fluency, vocabulary, grammar, and comprehension. This rubric was selected because it enables a detailed and objective assessment of students’ speaking performance across multiple dimensions. The same test format and scoring rubric were used in both the pre-test and post-test to ensure consistency and reliability of the data. Students’ responses were audio-recorded to support accurate evaluation.

Tabel 1 Assessment Rubric (Adapted from brown)

Data Collection Procedures

Data collection in this research was carried out in a structured manner in accordance with a one-group pre-test and post-test research design. The data were obtained through speaking assessments administered before and after the application of Inquiry-Based Learning (IBL) using Chapter 1 “About Me” from the English for Nusantara textbook.

1. Pre-test

The pre-test was conducted to identify students’ baseline speaking proficiency before the implementation of Inquiry-Based Learning. In this stage, each student individually completed a speaking test adapted from Chapter 1 "About Me" in English for Nusantara. Students were assessed one by one in front of the researcher to ensure that each participant's speaking performance was evaluated independently. The test consisted of several guiding questions, such as "Can you introduce yourself?", "What are your hobbies?", and "Can you describe your best friend?". These prompts required students to introduce themselves, explain their hobbies, or describe their best friend. Each student delivered an oral performance lasting approximately 2–5 minutes without relying on a written script. An analytic scoring rubric adapted from Brown [3] was used to evaluate students' speaking performance across five components: pronunciation, fluency, vocabulary, grammatical accuracy, and comprehension. The consistent use of this rubric throughout the research ensured the reliability and comparability of the assessment results.

2. Treatment

The treatment phase was conducted in two meetings by implementing the Inquiry-Based Learning (IBL) approach. The instructional process followed five main stages: questioning, investigating, creating, presenting, and reflecting. In the first treatment, which focused on describing people, the learning activities began with the questioning stage, where the teacher introduced the topic by showing pictures of people with different appearances, such as public figures, cartoon characters, or students. The learning process began with the questioning stage, where the researcher used several guiding questions to activate students’ prior knowledge and stimulate their interest in the topic. Students were encouraged not only to respond but also to formulate their own questions, particularly concerning new vocabulary items. During the investigation stage, students collaborated in groups of three to four members to examine descriptive expressions and sentence patterns using a range of learning materials, such as texts and videos. The creating stage then required each group to produce a short oral description of a selected individual, including a friend, a public figure, or themselves, utilizing the language features they had explored. In the presenting stage, groups delivered their descriptions to the class, followed by peer responses and questions. The lesson concluded with a reflection stage in which students and the teacher discussed common challenges experienced during the activities, including issues related to pronunciation, vocabulary selection, and sentence construction, while also reflecting on the knowledge and skills acquired throughout the learning process.

In the second treatment, which focused on daily activities, similar stages of Inquiry-Based Learning were applied. The lesson began with the questioning stage, where the teacher asked questions such as “What do you do in the morning?” and “Why do you do it?” to activate students’ prior knowledge. In the investigating stage, students analyzed example texts or videos related to daily routines and identified commonly used expressions. During the creating stage students made talks about what they do every day. For example they said things like "I wake up at 5 then I take a shower." In the presenting stage students practiced speaking with a partner. Did short conversations based on what they learned from the textbook. Finally in the reflecting stage the teacher gave feedback on how students spoke looking at how smoothly they talked how clearly they pronounced words and how correct their grammar was. Meanwhile students thought about what was hard, for them while they were learning.

3. Post-test

Following the completion of the treatment sessions, a post-test was administered to assess students’ speaking ability after the implementation of Inquiry-Based Learning, in which the tasks were adapted from Chapter 1 “About Me” in the English for Nusantara textbook for seventh-grade students and designed to be parallel with the pre-test in terms of format and level of difficulty while using slightly different prompts within the same thematic scope, consisting of guiding questions such as “Can you introduce your best friend?”, “What are your friend’s hobbies?”, and “What activities do you usually do together?”, which aimed to encourage students to express personal information in a communicative context, where students were required to deliver a short oral performance of approximately 1 to 5 minutes without using written notes, and their performances were assessed using the same analytic speaking rubric adapted from Brown, covering pronunciation, fluency, vocabulary, grammatical accuracy, and comprehension, to ensure that any improvement in speaking performance could be attributed to the instructional treatment rather than differences in assessment criteria.

Speaking Test Material

The teaching materials used in this study were adapted from Chapter 1 "About Me" in the English for Nusantara textbook for seventh-grade students. Although the textbook originally presents several listening activities, in this research the materials were modified and implemented as speaking activities to support the objectives of Inquiry-Based Learning (IBL). The materials provided contextual topics that encouraged students to introduce themselves, describe people, and talk about daily activities through oral communication. These materials were integrated into the five stages of Inquiry-Based Learning, namely questioning, investigating, creating, presenting, and reflecting, to provide students with meaningful opportunities to practice speaking while improving pronunciation, fluency, vocabulary, grammar, and comprehension.

Pict 1. Student Performance Materials

The speaking test was adapted from Chapter 1 “About Me” in English for Nusantara, particularly Worksheet 1.2, which introduces students to the topic of self-introduction. The worksheet presents a character named Galang and requires students to identify personal information, including name, origin, age, school, sibling, hobby, and address. This activity familiarizes students with the language expressions and vocabulary commonly used in introducing themselves. After completing the worksheet, students were instructed to perform an individual oral self-introduction by using similar information about themselves instead of Galang. They answered guiding questions such as “Can you introduce yourself?”, “Where are you from?”, “How old are you?”, “What are your hobbies?”. Each student delivered a spoken performance lasting approximately 2–5 minutes without using a written script. Their speaking performances were then assessed using an analytic scoring rubric adapted from Brown , covering pronunciation, fluency, vocabulary, grammatical accuracy, and comprehension.

Pict 2 Student Performance Materials

The second learning material used during the implementation of Inquiry-Based Learning was adapted from Comic Strip 1.2 in Chapter 1 About Me of English for Nusantara. The comic strip presents a conversation among three students, Galang, Monita, and Andre, who introduce themselves and exchange personal information during their first day at school. The dialogue demonstrates simple interpersonal communication through greetings, introductions, and discussions about personal interests. The comic strip provides contextual examples of English expressions used to introduce new classmates, respond politely, and maintain a conversation. The interaction includes exchanging names, introducing another person, expressing hobbies and interests, and ending a conversation appropriately. These language functions support students in developing both speaking accuracy and communicative competence. During the Inquiry-Based Learning process, students first listened to the audio while observing the comic strip to understand the context of the conversation. They then identified important information, discussed unfamiliar vocabulary and expressions, formulated questions about the dialogue, and analyzed the communicative functions used by the characters. Based on their observations, students created and practiced similar conversations by using their own personal information and experiences. Finally, students performed their dialogues orally to demonstrate their speaking ability.

Pict 3 Student Performance Materials

The learning material used during the implementation of Inquiry-Based Learning was adapted from Comic Strip 1.4 in Chapter 1 About Me of English for Nusantara. The comic strip presents a dialogue between two characters, Galang and Andre, who introduce themselves to each other using simple English expressions. The conversation covers several aspects of personal identity, including name, age, place of residence, hobbies, and family members. The comic strip was used as a contextual learning resource to provide students with authentic examples of self-introduction and interpersonal communication. Students first listened to the recorded dialogue while following the comic strip to understand the expressions and pronunciation used by the characters. They then identified important information from the conversation, discussed the meaning of unfamiliar vocabulary, and analyzed the expressions used for introducing oneself and asking for personal information. Following the Inquiry-Based Learning stages, students were encouraged to observe the dialogue, formulate questions, investigate the language expressions, and practice creating their own conversations by adapting the information to their personal identities. Finally, students performed their dialogues individually or in pairs to demonstrate their speaking ability in introducing themselves and interacting with others.

Data Analysis

The data analysis in this study used a quantitative approach to examine the effect of Inquiry-Based Learning on students' speaking skills.

Students’ speaking performance in both the pre-test and post-test was evaluated using an analytic scoring rubric adapted from Brown [3], which includes five components: pronunciation, fluency, vocabulary, grammar, and comprehension, each rated on a scale of 1 to 5. The total speaking score for each student was obtained by summing the scores of all five components, resulting in a maximum score of 25. To standardize the results, the total score was converted into a scale of 0–100 using the following formula:

The data analysis involved calculating individual pre-test and post-test scores, followed by computing the mean scores of both tests. Gain scores were then calculated by subtracting pre-test scores from post-test scores to determine the improvement in students’ speaking performance. Prior to hypothesis testing, the normality of the data was examined using the Shapiro-Wilk test. If the data were normally distributed, a paired sample t-test was conducted to determine whether there was a significant difference between pre-test and post-test s cores. Otherwise, a non-parametric alternative, namely the Wilcoxon signed-rank test, was applied.

The collected data were analyzed by comparing students’ scores from the pre-test and post-test. The analysis procedures included calculating individual pre-test and post-test scores, computing the mean scores for both tests, and determining score gains by subtracting pre-test scores from post-test scores. The comparison of mean scores was used to identify improvements in students’ speaking skills following the implementation of Inquiry-Based Learning.

An increase in students’ post-test scores was interpreted as evidence supporting the effectiveness of Inquiry-Based Learning in improving speaking skills. The observed score gains indicated positive developments in students’ oral abilities, especially in aspects targeted by Inquiry-Based Learning, such as communicative fluency, learner confidence, and meaningful language use. These results were further examined in relation to the principles of speaking assessment outlined by Brown [3],which emphasize the importance of validity, reliability, and recency in classroom assessment.

III. Result and Discussion

Result

This section presents the findings of the study, including descriptive statistics, normality testing, and hypothesis testing:

Tabel 2 Descriptive Statistic

The descriptive statistics of students’ speaking scores are presented in Table 1. The mean score of the pre-test was 43.00, while the mean score of the post-test increased to 81.78. This indicates a substantial improvement in students’ speaking performance after the implementation of Inquiry-Based Learning. Furthermore, the standard deviation decreased from 14.732 in the pre-test to 6.302 in the post-test, suggesting that students’ scores became more consistent after the treatment.

Tabel 3 Tests of Normality

The normality of the data was examined using the Shapiro-Wilk test. The results showed that the significance value for the pre-test was 0.050, indicating that the data were normally distributed. However, the post-test data showed a significance value of 0.001, which is lower than 0.05, indicating that the data were not normally distributed.

Tabel 4 Hypothesis Test Summary

Due to the violation of normality in the post-test data, a non-parametric test, namely the Wilcoxon signed-rank test, was conducted to examine the significance of the difference between pre-test and post-test scores. The result showed that the significance value was 0.000, which is lower than 0.05. This indicates that the null hypothesis was rejected, meaning that there is a statistically significant difference between students’ pre-test and post-test scores.

In addition, a paired sample t-test was also conducted, which showed a significance value of 0.000 and a mean difference of -38.778, indicating that students’ post-test scores were significantly higher than their pre-test scores. These results consistently demonstrate that there was a significant improvement in students’ speaking performance after the implementation of Inquiry-Based Learning.

Disscussion

The findings of research were found tha data showed that the implementation of Inquiry-Based Learning significantly improved students’ speaking skills. This was indicated by the increase in students’ mean scores from 43.00 in the pre-test to 81.78 in the post-test. In addition, the result of the Wilcoxon signed-rank test showed a significance value of 0.000, which was lower than 0.05, indicating that there was a statistically significant difference between students’ pre-test and post-test scores. These findings suggest that Inquiry-Based Learning had a positive effect on students’ speaking performance in the classroom.

The improvement in students’ speaking skills may be attributed to the characteristics of Inquiry-Based Learning, which emphasize active participation, questioning, investigation, collaboration, and meaningful communication during the learning process [1]. Through inquiry-based activities, students were encouraged to explore ideas, discuss topics collaboratively, and express their opinions orally in English. These activities provided students with more opportunities to practice speaking actively compared to conventional teacher-centered learning methods. As a result, students became more confident in expressing their ideas and participating in classroom communication.

The implementation of the five stages of Inquiry-Based Learning, namely questioning, investigating, creating, presenting, and reflecting, also contributed to the improvement of students’ speaking skills. During the questioning stage, students were stimulated to think critically and respond to guiding questions related to real-life contexts. In the investigating stage, students worked collaboratively to explore vocabulary, expressions, and information needed for speaking tasks. The creating and presenting stages encouraged students to construct spoken texts and present their ideas orally through dialogues, presentations, and group discussions. Finally, the reflecting stage allowed students to evaluate their speaking performance and receive feedback from both the teacher and peers. These structured learning activities created a supportive learning environment that promoted students’ communicative competence and speaking confidence [3].

The findings of this study are also supported by Collaborative Learning Theory, which emphasizes that social interaction and peer collaboration play an important role in developing students’ communication skills [14] through collaborative inquiry-based activities, students were able to exchange ideas, negotiate meaning, and practice speaking in meaningful social contexts. In addition, the findings are consistent with Problem-Based Learning Theory, which highlights the importance of real-life problems and active student engagement in the learning process [16] by participating actively in inquiry-oriented speaking activities, students developed not only their speaking ability but also their critical thinking and confidence in communication.

Moreover, the findings of this study are in line with previous studies related to Inquiry-Based Learning and speaking instruction. Previous research conducted by Nurhayati [14] ound that Inquiry-Based Learning encouraged students’ active communication and classroom interaction. Similarly, Valentine [12] reported that interactive learning techniques could improve students’ speaking performance through collaborative activities and discussions. The consistency between the findings of this study and previous studies indicates that Inquiry-Based Learning is an effective instructional approach for improving students’ speaking skills, particularly in junior high school classrooms.

In addition, the use of the English for Nusantara textbook supported the successful implementation of Inquiry-Based Learning in this study. The textbook provided communicative and inquiry-driven learning activities that were relevant to students’ daily lives and language abilities [5]. These contextual learning materials encouraged students to engage actively in speaking activities and helped create meaningful learning experiences in the classroom. Therefore, the integration of Inquiry-Based Learning and English for Nusantara can be considered an effective strategy for supporting the implementation of the Merdeka Curriculum and enhancing students’ speaking competence in English learning.

IV. Conclusion

This study concluded that Inquiry-Based Learning had a positive effect on junior high school students’ speaking skills. The implementation of Inquiry-Based Learning created meaningful learning experiences by encouraging students to actively participate in questioning, investigating, creating, presenting, and reflecting activities. These learning experiences provided students with greater opportunities to practice speaking, express their ideas, and develop confidence in using English for communication. Furthermore, the English for Nusantara textbook supported the implementation of Inquiry-Based Learning by providing contextual and communicative learning materials that were appropriate for students’ needs. Therefore, the integration of Inquiry-Based Learning and the English for Nusantara textbook can be considered an effective instructional approach for improving students’ speaking skills and supporting the implementation of the Merdeka Curriculum at the junior high school level.