With Common Core State Standards (CCSS), all students are held to the same high expectations, including students learning English and other learners who may have academic difficulties. Many students learning English have trouble writing and need effective writing strategies to meet the demands the standards present. Ten fourth and fifth grade students learning English (6 girls and 4 boys), whose home language was Spanish, participated in a multiple baseline design across three small groups of participants with multiple probes during baseline. In this study, self-regulated strategy development (SRSD) for opinion writing using students’ own ideas was evaluated. Students who participated in this study demonstrated an increase in: the number of persuasive elements (e.g. premise, reasons, elaborations, and conclusion) included in their essays, overall essay quality, and the number of linking words used when writing opinion essays using their own ideas. Additionally, students’ knowledge of the writing process and opinion-writing genre improved. Students found the instruction to be socially acceptable. Limitations and directions for future research are discussed.