Teaching spelling is controversial because teaching approaches vary considerably in the contemporary classroom. Teachers may privilege visual over linguistic strategies, select words based around themes or let students choose spelling words, rather than focus on the explicit teaching of phono-morphological structures of words. A nine-week intervention spelling project that included the phono-morphological structure of words and contextualised sentence dictation was designed to support Year 2 students in a NSW school and is described here. The intervention aimed to support all students including those with learning difficulties and an English as an Additional Language (EALD) background, within a mainstream setting. The high-impact instruction was cumulative in design; it provided simple to more difficult target spellings; massed practice during instruction; distributed practice during generalisation; editing and dictation tasks; and continuous formative and summative assessment. Post-sentence dictation results showed that the students who received the intervention had improvements with modest to strong effect sizes.