Abstrak. Penelitian tindakan kelas ini bertujuan untuk mengetahui peningkatkan aktivitas dan hasil belajar peserta didik dengan menggunakan metode demonstrasi dan diskusi -informasi pada materiAsam Basa dan Garam. Penelitian dilaksanakan di kelas VII B SMP Negeri 15 Semarang pada semester genap tahun pelajaran 2014/2015. Penelitian dilaksanakan dalam dua siklus dengan menerapkan metode demonstrasi disertai diskusi-informasi sesuai dengan perencanaan. Berdasarkan hasil analisisdengan menggunakan angket, observasi, wawancara dan tes maka diperoleh peningkatan hasil belajar yang signifikan.Peningkatan aktivitas siswa dapat dilihat berdasarkan penilaian diri dan pengamat pada siklus I dan siklus II yaitu dari 87,3% menjadi 96,3%.Sedangkan peningkatan ketuntasan belajar klasikal pada siklus I dan II yaitu dari 59,4% menjadi 87,5%. Berdasarkan hasil penelitian tersebut maka dapat disimpulkan penggunaan metode demonstrasi dapat meningkatkan aktivitas siswa dalam pambelajaran dan hasil belajar siswa.Kata kunci: Metode Demonstras, Aktivitas Siswa, Hasil belajar.Abstract. This classroom action research aimed to find out the improvement of students' activities and their learning outcomes by using demonstration method and discussion/gathering information on Acids, Bases, and Salts topic. The subjects of the study were students of Class VII B SMP Negeri 15 Semarang on even semester in 2014/2015. It was conducted in two sessions; they were demonstration method and discussion/gathering information in accordance with the planning. According to the result of questionnaire, interview and test, there was a significant improvement. The improvement of students' activities was found out by the result of a self-assessment and an observation in the session I and the result of discussion in the session II from 87,5% to 96,3%. Those activities were including listening, writing, questioning, doing assignments, discussing, and presentation. While the improvement of classical students' learning outcomes were found out by the result of session I and session II from 59,4% to 87,5%. According to the result of the study, it could be concluded that the use of demonstration method was able to improve students' activities in their learning activities and outcomes.