This research sought to investigate the effects of instructional materials used at community resource centers on adult literacy learners in community development activities with a specific focus on Nyamira North Sub-County, Kenya. The study was guided by the constructivism theory of learning. It employed the descriptive survey design where a sample of 254 learners was drawn from a population of 492 adult learners in the study area using the stratified random sampling method. Questionnaires were administered to elicit information from the respondents. The collected data were analyzed using descriptive statistical methods. From the findings, there was a clear indication that textbooks and sewing machines were more available and adequately utilized. Other resources like computers, projectors, ovens, banana ripening chambers, and videos were least available and inadequate. Results further showed that most of the adult learners were involved in small-scale farming as their main economic activity with most of their products was selling them to the market in raw form. Some learners were also involved in natural resource management activities with the majority of them planting trees, water resources management, bridges, and path construction. The study recommended that to diversify the livelihoods of the communities in the study area, the Directorate of Adult Education should provide diverse instructional materials such as ICT facilities and equipment that which will impart value addition skills to the learners.