ABSTRAK
Penelitian ini bertujuan untuk mengetahui: karakteristik, tingkat kevalidan dan reliabilitas instrumen, efektivitas penilaian, dan kepraktisan penilaian melalui authentic assessment berbasis scientific approach dengan tema suhu dan perubahannya.
Metode penelitian menggunakanResearch And Development (R & D) mengacu pada model Four D dari Thiagarajan, Semmel dan Semmel dengan tahapan define, design, develop, dan disseminate. Kegiatan penelitian diawali dengan menyusun silabus, Rencana Pelaksanaan Pembelajaran (RPP), Lembar Kegiatan Peserta Didik (LKPD), bahan ajar, dan alat evaluasi yang divalidasi oleh Tim ahli. Pengujian keefektifan penerapan instrumen penilaian yang dikembangkan menggunakan analisis N-gain ternormalisasi. Data validitas dan reliabilitasinstrumen penilaian dianalisis dengan deskriptif persentase. Data hasil belajar dianalisis dengan deskriptif persentase dan peningkatan hasil belajar dihitung dengan N-gain ternormalisasi.
Hasil validasi ahli dan praktisi terhadap instrumen pada tiga aspek yaitu sintak, perangkat pembelajaran, dan perangkat evaluasi authentic assessment, rataan ketiga aspek tersebut  memperoleh nilai sebesar 94,25% dengan kategori sangat baik. Persentase hasil belajar peserta didik pada kompetensi  sikap, keterampilan, dan pengetahuan mencapai ketuntasan klasikal = 80%. Rataan nilai sikap kelas eksperimen yaitu 3,22 mencapai kategori baik, rataan nilai keterampilan pada kelas eksperimen adalah 3,14 mencapai kategori baik, dan rataan nilai pengetahuan pada kelas eksperimen adalah 85,5 mencapai kategori baik. Hasil penelitian menunjukan bahwa instrumenauthentic assessment berbasis scientific approach valid dengan rerata nilai validator 3,77 pada kategori sangat baik dengan koefisien reliabilitas untuk setiap kompetensi penilaian mencapai kategori tinggi atau sangat reliabel. Implementasi perangkat authentic assessment berbasis scientific approach efektif untuk mencapai ketuntasan hasil belajar karena mencapai ketuntasan klasikal = 80%, hasil uji keefektifan ditinjau dari analisis N-Gain ternormalisasi sebesar 0,73 mencapai kategori tinggi. Penerapan authentic assessment berbasis scientific approach praktis ditinjau dari rerata respons peserta didik dan guru mencapai kategori tinggi.
Kata kunci : Authentic Assessment, Scientific Approach, Hasil Belajar
ABSTRACT
This research is aimed to know: The characteristics, the instrument validity and reliability level, the assessment effectiveness through, and the assessment practice of scientific approach based authentic assessment with the theme of tempeature and its changing.
This method of this research is (R & D)referring to the model of  four D (define, design, develope, and disseminate) from Thiagarajan, Semmel and Semmel. The research activity is initialed with arranging syllabus, lesson plan, worksheet, learning material, and evaluation instrument validated from the expert team. The effectiveness test of learning instrument implementation which is developed by using N-gain analyzed. The validity and reliability data of learning instrument is analyzed by using descriptive percentage. The data of learning result is calculated by using normalized gain.
The result of validation from the expert and practical validator viewed from three aspects; i.e. syntax, learning instrument, and evaluation instrument of authentic assessment; the average of them got 94,25% with an excellent category. The presentage result from attitude, skill, and knowledge got classical minimum score is = 80%. The average of attitude score in the experiment class is 3,22 in a good category; the average of skills score in experiment class is 3,14 in a good category; and the average of knowledge score in the experiment class is 85,5 in a good category. The finding result shows that the instrument of scientific approach based authentic assessment is valid with the score of validator is 3,77 in an excellent category with coefficient reliabilty  in a good reliable. The instrument implementation of scientific approach based authentic assessment is effective to reach the minimum score of learning result because the classical minimum score is = 80%, the result of instrument effectivity based on gain score is 0,73 in a high category level. The implementation of scientific approach based authentic assessment is effective viewed from the average of student and teacher’s response reaches high category.
Keywords: Authentic Assessment, Scientific Approach, Learning Outcome.