Penelitian ini bertujuan untuk mendeskripsikan keefektifan assessment for learning dalam pembelajaran guided inquiry untuk meningkatkan keterampilan proses sains siswa.  Keefektivan pembelajaran dapat ditinjau dari tiga aspek yaitu hasil deskripsi keterlaksanaan pembelajaran, peningkatan keterampilan proses sains, dan respon siswa terhadap pembelajaran. Adapun jenis dan rancangan penelitian yang digunakan adalah Pre Experimental Design dengan rancangan penelitian One group pretest-posttest. Penelitian dilakukan di SMPN 3 Sidoarjo dengan jumlah sampel yang diambil sebanyak 28 siswa dari kelas VII-G. Teknik pengumpulan data menggunakan tiga metode yaitu metode tes untuk keterampilan proses sains, metode observasi untuk keterlaksanaan pembelajaran, dan metode angket untuk respon siswa dalam pembelajaran. Hasil penelitian mendeskripsikan bahwa pelaksanaan assessment for learning dalam pembelajaran guided inquiry  terlaksana dengan baik yang diperoleh dari hasil rata-rata keterlaksanaan pembelajaran sebesar 3,38. Selain itu, pelaksanaan assessment for learning dapat meningkatkan pemahaman siswa yang diperoleh dari persentase respon siswa sebesar 96,43% dan meningkatkan keterampilan proses sains siswa yang diperoleh dari n-Gain Score sebesar 0,6 dengan kategori sedang. Demikian, dapat ditarik simpulan bahwa assessment for learning dalam pembelajaran guided inquiry efektif dalam meningkatkan keterampilan proses sains siswa pada materi pemisahan campuran.

Kata kunci : Efektivitas pembelajaran, assessment for learning dalam pembelajaran guided inquiry, keterampilan proses sains

This research is aimed to description the effectiveness of assessment for learning in guided inquiry learning to improving students' science process skills. The effectiveness of learning can be observed from three aspects: the results of the description of the implementation of learning, improvement of science process skills, and students’ respones to learning. The type and design of the study used was Pre Experimental Design with the one group pretest-posttest research design. The study was conducted at SMPN 3 Sidoarjo with a total sample are 28 students from VII-G class. The data collection techniques were obtained by using three methods including the test method on science process skills, the observation method on the implementation of learning, and the questionnaire method for students’ responses to learning. The results of study describe that the implementation of assessment for learning in guided inquiry learning was carried out well which was obtained from the results of the average learning implementation of 3,38. In addition, the implementation of assessment for learning can improve student understanding obtained from the percentage of stident responses of 96,43% and improve students, science process skills obtained from the n-Gain Score of 0,6 with the medium category. Thus, it can be concluded that assessment for learning in guided inquiry learning is effective in improving students' science process skills in mixed separation material.

Keywords: learning effectiveness, assessment for learning in guided inquiry learning, science process skill