Penelitian ini bertujuan untuk mengetahui pengaruh model pembelajaran CORE (Connecting, Organizing, Reflecting, Extending) berbantuan mind map terhadap pemahaman konsep matematika siswa pada kelas VIII SMP Negeri 4 Singaraja tahun ajaran 2016/2017. Populasi penelitian adalah siswa kelas VIII SMP Negeri 4 Singaraja sebanyak 316 orang siswa. Sampel ditentukan dengan teknik random sampling yang sebelumnya telah dilakukan uji kesetaraan menggunakan uji ANAVA satu jalur sehingga sebanyak 2 kelas terpilih sebagai sampel dengan ukuran sampel 70 siswa yaitu kelas VIII B8 dan VIII B7. Penelitian ini merupakan penelitian semu dengan desain penelitian menggunakan post-test only control group. Data pemahaman konsep matematika siswa diperoleh melalui tes uraian. Hasil penelitian data diperoleh rata-rata skor pemahaman konsep matematika siswa kelas eksperimen adalah 42,675 sedangkan pada kelas kontrol adalah 31,933. Selanjutnya, data tersebut di analisis menggunakan uji U Mann-Whitney yang dikonversi ke Z karena  sampel yang besar sehingga berdistribusi normal dengan taraf signifikansi 5%. Hasil analisis menunjukkan  nilai |Ztabel(1,645)|< |Zhitung(-2,8623|. Dengan demikian H0 ditolak sehingga, pemahaman konsep matematika siswa yang mengikuti pembelajaran dengan model pembelajaran CORE berbantuan mind map lebih baik dari pemahaman konsep matematika siswa yang mengikuti pembelajaran dengan pembelajaran konvensional. Sehingga dapat disimpulkan bahwa model pembelajaran CORE berbantuan mind map berpengaruh positif terhadap pemahaman konsep siswa kelas VIII SMP Negeri 4 Singaraja.Kata kunci: mind map, model pembelajaran CORE, kemampuan pemahaman konsep matematika.

Non-routine mathematical problems are complex problems that require a level of creativity and uniqueness in solving them. Classification students’ characteristics of solving non-routine problems have not been many researchers who provide an overview. This study aims to classify the characteristics of students’ problem solving skills. This type of research is a qualitative study involving five students of class VIII at SMP Negeri 1 Kintamani. Five students were selected through a purposive sampling technique on the condition that students of class VIII have high, medium and low mathematical skills. Data regarding non-routine mathematical problem solving students are collected through problem solving tests and supported by interview tests to obtain a picture of students’ ability to understand the questions along with an understanding of the answers that have been done. Data were analyzed with data reduction, data presentation, and data verification steps. Data that has been verified are analyzed using the constant comparison method. Characteristics of non-routine mathematical problem solving students can be classified into 4 levels, namely Level 1 (students’ understanding of problems along with mathematical problem solving is very lacking), Level 2 (Students’ understanding of problems less and students’ problem solving is lacking but able to plan problem solving), Level 3 (students ‘understanding of problems takes a long time and students’ problem solving is good), and Level 4 (students ‘understanding of problems is good and students’ problem solving is very good). Classification is obtained based on reference to problem solving according to Polya.