<![CDATA[This study aims to: (1) describe the results of ethnomathematics exploration in charcoal production activities as a source of mathematics learning context; (2) develop an e-worksheet based on ethnomathematics exploration using the Book Creator application on algebraic expression material for seventh-grade junior high school students; and (3) determine the validity and practicality level of the developed e-worksheet. This research is a Research and Development study using the 4D model (Define, Design, Develop, and Disseminate) limited to the Develop stage. The Define stage was carried out through needs analysis, curriculum analysis, learner characteristics analysis, concept analysis, and ethnomathematics exploration of charcoal production activities in Belah Village, Donorojo District, Pacitan Regency. The Design stage covered the design of content, layout, and research instruments. The Develop stage included product validation by nine validators (material, media, and language experts), product revision, and a limited trial involving seventh-grade students of SMP Negeri 1 Donorojo. Data were collected through observation, interviews, documentation, validation questionnaires, and student response questionnaires, then analyzed descriptively and quantitatively. The results show that: (1) the results of ethnomathematics exploration in charcoal production activities contain concepts of measurement, social arithmetic, and algebraic expressions that are contextualized into mathematics learning; (2) the e-worksheet developed with the Book Creator application contains material, learning activities, exercises, evaluation, and local cultural elements of charcoal production; (3) the validity level from material, media, and language experts obtained average scores of 4.58, 4.71, and 4.60 respectively, categorized as very valid, while the limited trial obtained an average practicality level of 76.41%, categorized as practical. Thus, the ethnomathematics-based e-worksheet on charcoal production is feasible to be used as a learning medium for algebraic expression material in seventh grade junior high school.]]>
