<![CDATA[This study responds to the persistently low mathematical literacy of Indonesian secondary students and the limited availability of contextual, interactive teaching materials at SMAN 1 Seluma, Bengkulu. The purpose of the research was to develop a Student Worksheet (LKS) based on Problem Based Learning assisted by Kahoot! on the topic of Systems of Linear Equations in Three Variables (SLETV) and to describe its validity and practicality for fostering the mathematical literacy of grade X students. The study employed a research and development design following the ADDIE model, comprising analysis, design, development, implementation, and evaluation. Participants consisted of three expert validators (content, media, and language), two mathematics teachers, 12 students in a limited trial, and 74 students in a field trial, all selected through purposive sampling. Data were collected through observation sheets, interview guidelines, expert validation sheets, and teacher and student response questionnaires, and were analysed using quantitative descriptive techniques by converting scores into validity and practicality categories. The worksheet obtained average validation scores of 3.82 from the content expert, 3.78 from the media expert, and 3.78 from the language expert, all within the highly valid category. Practicality reached 96% from teacher responses and 96% from student responses, both categorised as highly practical. The developed worksheet is therefore declared valid and practical and is appropriate for use as teaching material to foster students' mathematical literacy.]]>
