This research is started by developed STS student-worksheet, validated and applied in senior high school chemistry class. The student worksheet was developed by using R & D with the ADDIE model following the STS syntaxes. The worksheet was designed based on popular issue in everyday life and provide solutions according to science and technology. The students were given a problem statement and asked to plan and to run experiments to solve the problem. They have to videotape their work and reported their finding to the teachers. The student worksheet was considered valid by the experts before being applied. The validation score was 93.90% with a very feasible and valid category. The score of student worksheet was 86.25% of expectation. The main students' score on students' activities in class 95.31. Teacher and students gave positive responses to STS learning as shown score of positive respond reaching nearly maximum (94.50%). Nearly all agree that the student worksheet can be used as teaching material in chemistry learning.