Penelitian ini dilatar belakangi dengan ditemukan beberapa masalah mengenai modul ajar yang digunakan pada pembelajaran kurikulum merdeka. Penelitian ini merupakan penelitian pengembangan research and development (R&D) dengan melakukan beberapa langkah sesuai kebutuhan yaitu 5 langkah meliputi (1) analisis, (2) desain, (3) pengembangan, (4) implementasi, (5) evaluasi yang bertujuan untuk mengembangkan modul ajar berbasis problem based learning(pbl). Modul ajar yang dikembangkan diuji kelayakan oleh ahli materi, ahli bahasa, dan ahli media, guru kelas IV SDN 1 Ciomas, guru kelas IV SDN Dukuhdalem Ciawi, dan guru kelas IV SDN Dukuhdalem. Instrumen yang digunakan untuk pengujian efektivitas modul ajar yaitu uji efektivitas. Hal ini didasari oleh hasil validitas validator dengan hasil perhitungan Aiken’s pada indicator instrument ahli materi Aiken’s dengan rata-rata 0.8666 yang dapat diinterpretasikan tinggi, indicator instrument ahli bahasa dengan rata-rata 0.7333 yang dapat diinterpretasikan sedang, indicator instrument ahli media dengan rata- rata 0.7333 dapat diinterpretasikan sedang. Hasil rekapitulasi dari terhadap penilaian modul ajar ahli materi sebesar 90% berada pada kualifikasi sangat layak. Hasil validasi ahli bahasa sebesar 80% berada pada kualifikasi layak. Hasil validasi ahli media sebesar 80% berada pada kualifikasi layak.

This research was motivated by the discovery of several problems regarding the teaching modules used in independent curriculum learning. This research is research and development (R&D) research by carrying out several steps according to needs, namely 5 steps including (1) analysis, (2) design, (3) development, (4) implementation, (5) evaluation which aims to develop a module teaching based on problem based learning (PBL). The teaching modules developed were tested for feasibility by material experts, language experts and media experts, class IV teachers at SDN 1 Ciomas, class IV teachers at SDN Dukuhdalem Ciawi, and class IV teachers at SDN Dukuhdalem. The instrument used to test the effectiveness of teaching modules is the effectiveness test. This is based on the results of the validity of the validator with the results of Aiken's calculations on the Aiken's material expert instrument indicator with an average of 0.8666 which can be interpreted as high, the linguist instrument indicator with an average of 0.7333 which can be interpreted as medium, the media expert instrument indicator with an average of 0.7333 can be interpreted as moderate. The recapitulation results from the assessment of the material expert teaching module were 90% in very decent qualifications. The linguist validation results were 80% within the appropriate qualifications. Media expert validation results of 80% are in the proper qualifications.