Validation and Effectiveness of Interactive Digital Books

Study Case Validation and Effectiveness of Interactive Digital Books for Learning Exponential Functions at the College Level Michael Kurniawan (2018123456) University of Cincinnati, 2600 Clifton Ave, Cincinnati, OH 45221, United States kurniaml@mail.uc.edu Abstract The learning process in Calculus courses still relies heavily on conventional media, resulting in low student enthusiasm for lectures and poor problem-solving skills. To help students understand the material more easily, an Interactive Digital Book was developed. The purpose of this study was to develop and produce a high-quality Interactive Digital Book based on the aspects of validity, practicality, and effectiveness in Calculus learning. This study was conducted at the Informatics Engineering Program at the University of Cincinnati using the Borg and Gall research and development model. The results of the study show that: (1) the Interactive Digital Book is considered highly valid with an average rating from media validators of 85.33%; (2) this product is very practical with an average student questionnaire score of 80.00%; and (3) the product is considered effective with a student learning completion rate of 95.83%. Thus, the Interactive Digital Book on the topic of Exponential Functions is suitable for use in Calculus learning. Keywords: Interactive Digital Book; Calculus; Exponential Function INTRODUCTION Learning resources include various learning tools that convey educational messages both visually and audiovisually, such as textbooks and other printed materials [1]. Along with technological advances in the United States, the use of digital books as teaching materials has increased. Digital books or e-books are books that are programmed and accessed through computers or other digital devices [2]. MICHAEL KURNIAWAN 1 Study Case The popularity of e-books has increased because of their interactive display, so that many people—both teenagers and adults—are more interested in using them. According to research [3], interactive learning that utilizes computer technology can increase the active participation of students because the learning process becomes more interesting and challenging. Based on observations and interviews with students in the Informatics Engineering Program at the University of Cincinnati, it was found that midterm exam scores in Calculus courses were relatively low. Only 37% of students scored above 70. Many students had difficulty understanding the concepts and applying formulas to various types of questions. The learning process still uses media such as blackboards and projector-based presentations. In addition, previous research [4] states that the low learning outcomes in Calculus may be due to students' lack of understanding of the relevance of this course to their field of study. The three main concepts in Calculus include limits, derivatives, and integrals. These three concepts play an important role in various fields, especially in the ever-evolving field of information technology. One effective way to help students understand Calculus material is to create interactive learning media that suits their needs. One alternative medium is the Interactive Digital Book, which not only contains material and sample questions, but also quizzes and quick tutorial videos on the topic of Exponential Functions. Previous research [5] on the development of Interactive E-Books for Digital Electronics courses showed that most students responded positively, and the product met the criteria for validity and suitability for use in learning. Similarly, research [6] on Interactive Digital Books for E-Learning courses proved that interactive digital books are suitable for use as a learning resource for technology education students. Another study by [7] entitled Innovation of Interactive Learning Media to Improve Learning Effectiveness in the Digital Era at Elementary Schools concluded that interactive media has the potential to create a more engaging learning experience, which in turn can increase student motivation to learn. This research focused on various types of digital learning media such as educational videos, simulations, educational games, and online learning platforms. Meanwhile, this research focused on the development of Interactive Digital Books for Calculus courses, with differences in the context of the material, location, and time of the research. From findings in the field, students tend to memorize formulas without MICHAEL KURNIAWAN 2 Study Case understanding the basic concepts in problem solving. This is particularly evident in the topic of Exponential Functions, where students have difficulty solving complex problems. Therefore, this study aims to develop a valid, practical, and effective Interactive Digital Book so that students can understand the material deeply and efficiently. METHOD This study uses the Research and Development (R&D) method, which is an approach that aims to produce a specific product while testing its effectiveness [8]. The product developed is an Interactive Digital Book on the topic of Exponential Functions in Calculus courses. The development model used is the Borg & Gall Model, which consists of ten stages: Research and Information Collecting, Planning, Develop Preliminary Form of Product, Preliminary Field Testing, Main Product Revision, Main Field Testing, Operational Product Revision, Operational Field Testing, Final Product Revision, and Dissemination and Implementation. This research was conducted at the Informatics Engineering Program, University of Cincinnati with 28 students participating. The research data consisted of primary and secondary data. Primary data was obtained through observation, interviews, and questionnaires to determine student needs. Secondary data was obtained from midterm exam results in the Calculus course. Data collection techniques included interviews, validation sheets, student response questionnaires, and learning outcome tests. Figure 1. Stages of the Borg and Gall Model MICHAEL KURNIAWAN 3 Study Case The Borg and Gall model has ten stages, but this study only used eight stages because the revision process was carried out once according to the researcher's needs. 1. Needs Analysis Stage (Research and Information Collecting) This stage includes curriculum analysis, media analysis, material analysis, student characteristic analysis, and previous learning outcome analysis. 2. Planning Stage The planning steps include preparing research instruments, selecting teaching materials, and preparing an initial description of the Interactive Digital Book. 3. Product Development Stage (Develop Preliminary Form of Product) At this stage, the instruments and initial products are validated, followed by a first revision to meet product quality standards. 4. Preliminary Field Testing Stage After the initial product is developed, it is validated by subject matter experts and media experts and tested on six students. The validation aims to assess the feasibility of the product using the following formula: 𝑉= 𝑇𝑆𝑒 × 100% 𝑇𝑆ℎ Explanation: V= Validity percentage TSe= Total empirical score (validator assessment) TSh= Total maximum score 5. Small Class Trial Trials are conducted on six students to assess the practicality and attractiveness of the product. The formula for calculating practicality validity is as follows [9]: 𝑉𝑝 = 𝑇𝑆𝐸𝑃 × 100% 𝑆𝑚𝑎𝑥 Explanation: V_p= Practicality validity TSEP= Total empirical practicality score S_max= Expected maximum score 6. Revision I (Main Product Revision) The first revision was carried out to refine the product before testing it in the next stage. After being declared valid by the validator, the product produced Draft II. MICHAEL KURNIAWAN 4 Study Case 7. Operational Field Testing (Operational Field Testing) This stage is the final formative evaluation. The sample consists of students in class B in the fall semester of the Informatics Engineering Study Program. Students take a learning outcome test, and learning effectiveness is calculated using formula [10]: 𝐾𝐵 = 𝑇 × 100% 𝑇𝑡 Explanation: KB= Percentage of learning completeness T= Total score obtained T_t= Total score 8. Final Product Revision The results of the field testing are used as the basis for refining the final product so that it is suitable for use in Calculus learning. This study did not proceed to the dissemination and implementation stages due to time and resource constraints. RESULTS AND DISCUSSION The product developed in this study is an Interactive Digital Book for Exponential Function material in Calculus courses. This study used the Research and Development (R&D) method with the Borg and Gall model. Field observations and unstructured interviews were used to identify the actual conditions of the Calculus learning process in the classroom. Based on these findings, there were several main problems, namely: students in the Informatics Engineering Program at the University of Cincinnati still found Calculus material—especially Exponential Functions—difficult to understand; interaction in the teaching and learning process was still low; and midterm exam scores were still in the low category. As a solution, a digital-based learning medium in the form of an Interactive Digital Book was developed to help students better understand Calculus material. A validation process was carried out to ensure the feasibility and accuracy of the developed product. The initial design of the Interactive Digital Book (Draft I) was submitted to media validators, who were lecturers from the Department of Mathematics Education at the University of Cincinnati, for assessment and feedback. Table 1. Validity Analysis Results MICHAEL KURNIAWAN 5 Study Case The analysis results show that the Interactive Digital Book obtained a validity level of 85.33%, thus categorized as highly valid [1]. The validator also provided several suggestions for product improvement, including: varying the background display to make it more attractive, adding instructions or arrow icons to open quiz links, and extending the quiz completion time from 5 seconds to 10 seconds. The small class trial phase involved six students. They were asked to use the Interactive Digital Book, take a learning outcome test, and fill out a response questionnaire to assess the practicality and effectiveness of the media. The learning process used the Microsoft Teams application, questions were sent via Google Form, and the digital book was accessed via a link shared by the researcher. Table 2. Small Class Practicality Analysis Results Based on the above analysis, the Interactive Digital Book obtained a practicality level of 68.88%, which is above the minimum threshold of 50% and is categorized as practical [2]. This shows that students responded positively to the use of interactive digital media, so the product is feasible to proceed to the field trial stage. To assess effectiveness, a learning outcome test was conducted using Google Forms after students studied the material through the Interactive Digital Book. Table 3. Small Class Effectiveness Analysis Results MICHAEL KURNIAWAN 6 Study Case All students scored above 70, with an average of 90%, indicating that the Interactive Digital Book is effective in improving learning outcomes on the topic of Exponential Functions. Based on the validation and small-scale trial results, the first revision (Revision I) was carried out according to the validator's input. Table 4. Product Revision for Cover MICHAEL KURNIAWAN 7 Study Case Improvements included color adjustments, increased graphic resolution, and the addition of interactive icons on the main page to facilitate navigation. The revision resulted in Draft II, which was then tested in the operational field test stage. The field test was conducted on 28 students in class B of the Informatics Engineering Program, University of Cincinnati. The digital book was accessed via a provided link, and after learning, students took a learning outcome test and filled out a response questionnaire. The validator's evaluation results showed that the Interactive Digital Book functioned well as an interactive learning medium that facilitated concept understanding. Students could study the material anytime and anywhere and take interactive quizzes to measure their understanding. Interaction between students and lecturers increased because the quizzes allowed for immediate feedback on learning outcomes. MICHAEL KURNIAWAN 8 Study Case According to research [3], interactive quizzes can improve students' ability to explore ideas, understand concepts, and foster creativity. Compared to conventional media such as PowerPoint via projector, the Interactive Digital Book is easier to use, interactive, and supports independent learning through video tutorials and animated guides. The practicality of the product was also tested through student response questionnaires in two stages, namely small class trials and field trials. In the small trial, the practicality percentage reached 68.88%, while in the field trial it increased to 80%, so it was categorized as very practical [4]. Table 5. Results of Field Test Practicality Analysis This shows that students find Interactive Digital Books interesting, easy to use, and useful as additional learning resources. Similar research by [5] shows that interactive multimedia-based teaching materials in mathematics courses are also very practical, with an average score of 87.55%. Table 6. Results of Effectiveness Analysis in Field Tests The average student score of 92.08 and the completion rate of 95.83% are well above the minimum threshold of 65% as stated by [6]. These results indicate that Interactive Digital Books on the topic of Exponential Functions are effective in improving student understanding and learning outcomes in Calculus courses. Another study [7] also supports these findings by stating that Android-based digital learning media can be accessed flexibly and provides an average feasibility of 82.3%, which is classified as very feasible. MICHAEL KURNIAWAN 9 Study Case CONCLUSION Based on the research results and discussion, the following conclusions were drawn: 1. The Interactive Digital Book for Calculus courses on the topic of Exponential Functions meets the criteria of being highly valid, with an average validator assessment score of 85.33%. 2. The developed product is considered highly practical, based on the results of the student response questionnaire, which reached 80%, making it suitable for use in learning activities. 3. In terms of effectiveness, the Interactive Digital Book meets the criteria for effectiveness, with a student learning completion rate of 95.83%. Thus, this Interactive Digital Book has been proven to be suitable for use as an interactive learning medium to support the understanding of the Exponential Function concept in Calculus courses in higher education institutions in the United States. REFERENCE MICHAEL KURNIAWAN 10 Study Case MICHAEL KURNIAWAN 11