This study aims to analyze wether (1) there is a difference in students' mathematical problem solving abilities and self regulation learning (SRL) taught contextual learning models with students taught cooperative learning models geogebra assisted; (2) there is an interaction between learning models with early mathematical abilities of students mathematical problem solving abilities and SRL. This research is a quasi experimental study. The population is the all of students of Santo Yoseph Private Middle School Medan grade VIII. The instruments used in this study are test mathematic problem solving abilities and questionnaire for SRL. The results of the study are there is difference in students mathematic problem solving abilities and SRL taught through geogebra assisted contextual learning models with students taught through geogebra assisted cooperative learning models and there is an interaction between learning and students' initial mathematical abilities towards students mathematical problem solving abilities and SRL.

The objectives of this study are to describe: 1) validity of learning tools developed based on the Realistic Mathematics Education approach; 2) practicality of learning tools developed based on the Realistic Mathematics Education approach; 3) the effectiveness of learning tools developed based on the Realistic Mathematics Education approach; 4) improvement of students' mathematical problem solving skills using learning tools based on the Realistic Mathematics Education approach that has been developed. This research is a development research. The development model used to develop learning tools in this study is the Dick and Carey development model. Before the field trial was conducted, the learning tools were validated by three experts and two practitioners. From the results of the validation, it was found that: (1) the learning tools developed were valid with the total average validity of student books (4.33), teacher books (4.28), learning implementation plans (4.42), and student worksheets (4.44). Subjects in this study were seventh grade students of senior high school (SMP) 1 Medan which consisted of two classes, namely VII-Herodotus as a trial class I and VII-Pythagoras as a trial class II. (2) learning tools that had been developed are effective, seen from classical learning completeness are fulfilled, in which ≥ 85% of students were passed, student activities within the specified tolerance limits, and students' responses to learning are in good categories; (3) the average increase in students' mathematical problem solving ability from trial I to trial II was 0.18 points, namely from 3.02 in the first trial to 3.20 in the second trial, with an increase in classical mastery learning 14%.

This study aims to: (1) analyze the differences in mathematical dispositions between students who are given a contextual learning model assisted by Geogebra and students who are given a model of cooperatif learning assisted by Geogebra at SMK Harapan Mekar 1 Medan, (2) analyze the interaction between learning and early mathematics ability (high, moderate, low) students towards improving students' mathematical communication skills at SMK Harapan Mekar 1 Medan, (3) analyzing the interaction between learning and the initial mathematics ability (high, medium, low) of students towards improving the mathematical disposition of students at SMK Harapan Mekar 1 Medan. The population of this study were all students of SMK Harapan Mekar 1 Medan in class X majoring in Automotive Mechanics and Computer Engineering. Samples were taken randomly from 6 classes, Students were selected as a sample of 2 classes, namely class X-2 as the experimental class I which was given the contextual learning model assisted by Geogebra and class X-3 as the experimental class 2 which was given the cooperative learning model assisted by Geogebra, with a total of 64 students. Data were analyzed using descriptive statistical analysis through two-way analysis. The results of this study indicate that: (1) There are differences in mathematical communication skills between students who are given a contextual learning model assisted by Geogebra and students who are given a cooperative learning model, (2) there are differences in mathematical disposition between students who are given a contextual learning model assisted by Geogebra and students who given a cooperative learning by Geogebra.

Feeling fed up and bored in learning mathematics occurs because of the imbalance between the right brain and the left brain, by forcing the brain to work very hard, can cause fatigue in the brain which results in a decrease in the concentration of students, especially mathematics. One method that can be used to increase concentration that can make the brain can relax in learning mathematics is to listen to classical music. The results of this study showed that there was a difference in the average grade of experimental classes that used accompaniment music while learning and control classes with learning without accompaniment music, obtained the average score of the experimental class posttest was 88.00 while the control class was 76.00 and the test calculation of the difference in the average score of the experimental class posttest and control classes was obtained tcount = 2.74 < ttable = 2.05, Which means that music affects concentration and improvement of student learning outcomes. Keywords: Music, Concentration, Learning Outcome