The purpose of this study is to explore the effect of Instructional Technology and Material Development (ITMD) course on the perceptions of teacher candidates' content development competencies with web 2.0 tools and the necessities of these tools. The embedded design, which is a type of mixed-method research design, was used in the study. The study was conducted within the scope of the ITMD course. In the course, teacher candidates were taught theoretical knowledge about instructional technology as well as practice including producing contents with web 2.0 tools. The participants of the study were 54 teacher candidates in a public university in the Department of Elementary Mathematics Teaching in Turkey. Results indicated that teacher candidates' content development competencies differed significantly between their pre- and posttest scores. However, although the pre-post difference in the score of their perceived necessities was in the expected direction, it was not significant. Results were discussed, and some implications were provided.