Author note — to cover

Cover the two interest schemes side by side: same principal and rate tabulated year by year, which pays more, why the gap widens, and exam questions asking for the difference after n years. Calculation methods are assumed from simple-interest and repeated-change; the compound formula and its decay twin live in Growth and decay. Both tiers. (R9, R16)

• Fluency — direct questions on simple versus compound interest, limited to this lesson's stated scope (4 questions).
• Application — use the same skill in unfamiliar or contextual questions without introducing a later method (4 questions).
• Check — questions built around the exclusions and likely misconceptions named in the lesson brief (4 questions).