Assess students' ability to analyze how changing a single phoneme in simple CVC words alters meaning. Tasks include identifying which phoneme (onset, nucleus, or coda) differs between minimal pairs, producing the resulting word after a specified phoneme substitution, explaining how the change affects meaning, and classifying the substitution as a consonant or vowel change. Use spoken, pictorial, and written CVC examples appropriate for Pre-K–Grade 2 (e.g., cat↔cap, pig↔big, bed↔bad). Focus on one-sound/one-letter changes only; exclude blends and multisyllabic items.