The Effect of Contextual Teaching and Learning Approaches on Learning Activities of Students in Science Subjects Subject Matter Changes in Form in Class V Students at School : Pengaruh Pendekatan Contextual Teaching and Learning Terhadap Aktivitas Belajar Siswa Mata Pelajaran IPA Materi Pokok Perubahan Wujud Pada Siswa Kelas V di Sekolah. acopen. 2022;6:10.21070/acopen.6.2022.2127. doi:10.21070/acopen.6.2022.2127