Developing multiple representation’s teaching materials assisted by blended learning to enhance students’ scientific argumentation skills

Electrolyte-nonelectrolyte and Colligative properties of solutions are materials which oriented by multiple representation of chemistry. In this research, the teaching materials were developed as online and offline materials. The development of teaching materials are based on Lee and Owen’s developing model which has five steps: 1) assessment/analysis, 2) design, 3) development, 4) implementation, 5) evaluation. Based on validity and legibility test results, the development on this research are valid and legible to be applied in learning process. The validity and legibility score frome measurement by the validators are 79% and from the students are 79%. Based on the effectiveness test results, it indicates that the teaching materials which have been developed are effective to raise the scientific argumentation skills for students showed by the pre-test post-test and n-gain scores. According to n-gain scores, it is known that 13 students’ scientific argumentation skills are increased in low level and 19 students’ are increased in medium level.