Tujuan dari penelitian ini adalah untuk mengembangkan bahan ajar tematik pada tema berbagai pekerjaan untuk siswa kelas IV SDN 041 Tarakan.
Jenis penelitian ini adalah Research and Development (R&D). Tahapan pengembangan meliputi penelitian pendahuluan, perencanaan pengembangan, pengembangkan bahan ajar dan evaluasi bahan ajar.
Hasil akhir penelitian ini adalah bahan ajar tematik pada tema berbagai pekerjaan untuk siswa kelas IV SDN 041 Tarakan. Validasi bahan ajar menggunakan instrument lembar validasi. Skor rata-rata bahan ajar yang telah divalidasi oleh ahli materi, ahli bahasa, dan ahli media diperoleh masing-masing 3.85 (kriteria baik), 4.58 (kriteria sangat baik), dan 4.40 (kriteria sangat baik). Sedangkan uji coba menggunakan lembar kuesioner dan catatan lapangan. Ada tiga uji coba : uji coba satu-satu, uji coba kelompok kecil, dan uji coba lapangan. Setiap uji coba mewakili siswa yang berkemampuan tinggi, sedang dan rendah. Uji coba satu-satu melibatkan 3 siswa, uji coba kelompok kecil melibatkan 9 siswa, dan uji coba lapangan melibatkan 21 siswa. Ketiga uji coba yang dilakukan mendapatkan respon positif artinya bahan ajar dapat dimengerti oleh siswa.
Berdasarkan data penelitian dapat disimpulkan bahwa bahan ajar tematik pada tema berbagai pekerjaan yang telah dikembangkan layak untuk digunakan siswa kelas IV di SDN 041 Tarakan.

Kata Kunci: Penelitian Pengembangan, Bahan Ajar, Tematik

The objective of this research was to develop Thematic Instructional Materials on the Theme of Various Jobs for the fourth Grade Students of SDN 041 Tarakan. The design of this research was Research and Development (R&D). The stages of development included preliminary study, planning, developing instructional materials, and evaluating the product of instructional materials. The final result of this research was a thematic instructional material on the theme the Theme of Various Jobs for the fourth Grade Students in SDN 041 Tarakan. Validation of instructional materials used validation sheet instrument. The mean score of instructional materials which were validated by material expert, linguist, and media expert were 3.85 (criteria good), 4.58 (criteria very good), and 4.40 (criteria very good) respectively. While try-out used a questionnaire and field note. There were three times try-out: one to one, small group, and field trials. Every try-out involved the students with high, moderate, and low level of ability. One to one try-out involved 3 students, small group try out involved 9 students, and field trials involved 21 students. All of three evaluations were conducted get response positive means that instructional materials can be used and can be understood by students. Based on the research data, it could be concluded that thematic instructional materials on theme of various jobs that had been developed was feasible to use for the fourth Grade Students of SDN 041 Tarakan. Keywords: Research and Development, Instructional Materials, Thematic