This study aimed to investigate the effects of the prediction-observation-explanation (POE) strategy using worksheets designed for the "living things and life" topic on conceptual understanding and science process skills (SPS) of students with mild intellectual disabilities (SMIDs). The sample consisted of 12 SMIDs (eight students for the main study and four students for the pilot study). The data were collected using SPS forms and interview protocols. The results showed that the POE worksheets enriched with active learning techniques positively developed SPS levels and helped the students overcome their alternative conceptions of the "living things and life" topic. The study also indicated that the SMIDs' differences and prior knowledge significantly impacted their learning outcomes. Accordingly, future studies should develop teaching activities and interventions based on SMID differences.