<![CDATA[This research aimed to describe the practicality and effectivity of SiMaYang Type II in acid-base topic. Population in this research was students of the 11th grade of through the MIA at SMAN 3 Bandar Lampung . The samples were the 11th grade of MIA1, MIA2, and MIA3 that were taken by using cluster random sampling. Quasi-experimental with one group pretest - posttest design was used as the method in this research. The practicality of SiMaYang Type II was known through implementation of lesson plans, students responses, teachers observation, and students activity for three classes that were classified as very high category. The effectivity of SiMaYang Type II was known increasing of self-efficacy for the samples that were high category. The value of n-Gain for the 11th grade of MIA1 was high category, and for 11th grade of MIA2 and MIA3 were medium category. Penelitian ini bertujuan mendeskripsikan kepraktisan dan keefektivan SiMaYang Tipe II pada materi asam basa. Populasi dalam penelitian ini seluruh siswa kelas XI MIA SMA Negeri 3 Bandar Lampung. Teknik pemilihan sampel yaitu cluster random sampling dan didapatkan sampel penelitian kelas XI MIA1, XI MIA2, dan XI MIA3. Metode penelitian yang digunakan adalah kuasi eksperimen dengan One Group Pretest-Postest Design. Hasil penelitian menunjukkan bahwa kepraktisan SiMaYang Tipe II yang ditunjukkan melalui keterlaksanaan RPP, observasi guru, respon siswa dan aktivitas siswa untuk ketiga kelas berkategori sangat tinggi. Keefektivan SiMaYang Tipe II yang ditunjukkan melalui peningkatan efikasi diri berkategori tinggi dan n-Gain XI MIA1 berkategori tinggi, sedangkan kelas XI MIA2 dan XI MIA3 berkategori sedang.Kata kunci: asam basa, keefektivan, kepraktisan, SiMaYang]]>
