Siti Hanijah Br. Saragih¹, Edi Syahputra², Syafari², Yuli Ragelia Sinaga^3,

This study aims to find out (1) validity of learning devices developed through the knisley mathematics learning model; (2) the effectiveness of learning devices developed through the knisley mathematics learning model; (3) the level of ability of students' mathematical understanding by using learning tools developed through the knisley mathematics learning model; (4) the level of students' mathematical disposition by using learning tools developed through the knisley mathematics learning model. Researchers develop learning tools in the form of teacher books, student books, student worksheets (LKS) and learning implementation plans (RPP). Validation of learning devices was carried out by 3 experts and two practitioners and obtained a total average value of validity at intervals of 4 ≤ Va < 5 with valid criteria. Mathematics learning devices developed through a technical mathematic model in improving the mathematical understanding and disposition skills of the developed SMP Swasta Tamora 2 students are effective. Based on the results of the ability of mathematical understanding of the test I and trial II, it was found that the average increase in students' mathematical comprehension ability was 4.12. Based on the results of the students 'mathematical disposition questionnaire in trial I and trial II it was obtained that there was an increase in students' mathematical disposition that is equal to 0.61.

understanding mathematical ability, 4-D model, learning devices development knisley mathematical learning model