<![CDATA[This research was based on the teachers constraint in assessing performance. This research was aimed to develop the performance assessment instruments which is easy to be used, and to describe the characteristics, realization, and methods of the developed performance assessment instruments. The research and development (RD) method by Borg and Gall was used in this research. The phases of this study were analysis needs, planning, development of product drafts, expert validation, field trials, networking teacher response, and the revision of the product. Based on teachers response about aspect of legibility, construction, and use of the product, it were categorized in very high. Development of performance assessment instrument on experiment effect of temperature on the reaction rate was produced a simple product and easy to be used.Penelitian ini didasarkan pada kendala guru dalam melakukan asesmen kinerja. Penelitian ini bertujuan untuk mengembangkan instrumen asesmen kinerja yang mudah digunakan serta mendeskripsikan karakteristik, pelaksanaan, dan metode instrumen asesmen kinerja pada praktikum pengaruh suhu terhadap laju reaksi. Metode penelitian yang digunakan adalah penelitian dan pengembangan (RD) menurut Borg dan Gall. Tahap-tahap penelitian ini adalah analisis kebutuhan, perancangan, pengembangan draf produk, validasi ahli, revisi, uji pemakaian produk, menjaring tanggapan guru dan revisi produk. Berdasarkan hasil tanggapan dari guru terhadap aspek keterbacaan, aspek konstruksi, dan aspek pemakaian produk memiliki kategori sangat tinggi. Penelitian dan pengembangan instrumen asesmen kinerja praktikum pengaruh suhu terhadap laju reaksi dihasilkan produk yang sederhana dan mudah digunakan.Kata kunci: asesmen kinerja, pengembangan, pengaruh suhu terhadap laju reaksi]]>
