Tujuan penelitian ini adalah menghasilkan worksheet yang valid, praktis, dan efektif sehingga dapat digunakan untuk melatihkan atau menyarangkan (nested) keterampilan berpikir dan keterampilan sosial pada pembelajaran IPA di SMP.  Worksheet model nested dikembangkan dengan menggunakan model ADDIE, yaitu analisis (analyze), rancangan (design), pengembangan (development), penerapan (implementation), dan evaluasi (evaluation). Peneliti melakukan uji coba 2 di SMP Negeri 2 Pungging Kabupaten Mojokerto tahun pelajaran 2017/2018 dengan rancangan penelitian one shoot-case study. Siswa melakukan praktikum dengan menggunakan worksheet model nested. Pengumpulan data menggunakan metode angket dan tes. Parameter yang diukur adalah validitas (validitas isi dan validitas konstruk), kepraktisan, dan efektivitas. Validitas isi dan validitas konstruk dinilai oleh tiga orang ahli. Worksheet model nested memenuhi syarat validitas isi karena nilai modus validitas isi sebesar 5 dengan kategori sangat valid. Worksheet model nested memenuhi syarat validitas konstruk karena nilai modus hasil penilaian validitas konstruk sebesar 5 dengan kategori sangat valid. Kepraktisan worksheet model nested diukur berdasarkan persentase skor  jawaban ya oleh siswa yang ditulis di dalam angket siswa terhadap penggunaan worksheet selama pembelajaran IPA. Worksheet model nested dinyatakan praktis karena persentase skor terendah hasil angket siswa 68,75 dengan kategori  positif. Efektivitas worksheet model nested diukur berdasarkan rata-rata jawaban benar pada keterampilan berpikir dan keterampilan sosial pada lembar worksheet dan  evaluasi pemahaman konsep siswa. Worksheet model nested dinyatakan efektif karena skor  rata-rata keterampilan berpikir ketiga worksheet di atas standar minimal 4,26 dengan kategori baik dan skor keterampilan sosial ketiga worksheet di atas standar minimal 2,13 dengan kategori baik. Rata-rata hasil  evaluasi  siswa  di atas standar minimal KKM 73 dengan pemahaman konsep tuntas. Hasil penelitian menunjukkan bahwa worksheet model nested yang dikembangkan memenuhi syarat valid, praktis, dan efektif untuk melatihkan keterampilan berpikir dan keterampilan sosial dalam pembelajaran IPA. Berdasarkan hasil uji Kruskal Wallis tidak ada satu pun nilai lebih kecil dari 0,05 sehingga menunjukkan adanya keajegan pada ketiga worksheet ketika diimplementasikan pada tiga kelas replikasi.

The aims of this study is to produce a nested model worksheet which valid, practical, and effective that is to train or nest thinking skill and social skill to science learning in junior high school. Nested model worksheet were developed using ADDIE models that is analysis, design, development, implementation, and evaluation. Researcher conduct has been tried out at SMP Negeri 2 Pungging Mojokerto districts of 2017/2018 academic year with the study design one shoot-case study. The students have practicum using nested model worksheet then fill out the questionnaires. The data collecting is using questionnaires and test. Measured parameters are validity (content validity and construct validity), practicality, and effectiveness. Content validity and construct validity were assessed by three expert. The nested model worksheet  qualifies the content validity because the modus score of content validity was 5 with very valid category. The nested model worksheet qualifies the construct validity because the modus score of construct validity was 5 with very valid category. The practicality of a nested model worksheet was measured based the percentage score of yes answer by students written in the student questionnaire on the use of worksheets during science learning. The nested models worksheet was declared practical because the lowest percentage score of the student questionnaire results was 68.75 with a positive category. The effectiviness of the nested model worksheet was measured based on the average correct answer to thinking skill and social skill on the worksheet sheet and evaluating students’ conceptual understanding. The nested worksheet model was declared effective because the everage score of the three of the  worksheet thinking skill above the standard was at least 4.26 with a good category and the social skill score of the three worksheet above the standart was at least 2.13 in the good category. The average student evaluation result above the minimum standart of KKM 73 with a understanding of the concept are complete. The results showed that the nested model worksheets developed fulfiled valid, practical, and effective requirements to train thinking skills and social skills in science learning. Based on the results of the Kruskal Wallis test there was none of the values was smaller than 0.05, thus indicating the existence of consistency in the three worksheet when implemented in three replication classes.