Reach for the Star

Growth decay and compound interest · Optional extension

L067 · Allow 10–15 minutes for learners ready to move on. Answers are available after an attempt.

Stretch

£1,000 grows 4% annually for three years. Find final value to the nearest penny.

Reveal a worked check after attempting

1000×1.04³=£1,124.86.

Deep challenge

A price rises 20% then falls 20%. Prove it does not return to the starting price.

Reveal a worked check after attempting

Multipliers 1.2×0.8=0.96; final price is 96% of original, 4% lower.

Recall & Review: feedback and extension integration

Lesson L067: Growth decay and compound interest

Objective: Model repeated percentage change, growth, decay and compound interest.

60-minute structure: 0-7 Connect & Check; 7-14 Share; 14-25 Present/model; 25-44 Apply route choice/practice; 44-52 independent exam-style check; 52-60 Recall & Review, WWW/EBI and next step.

What Went Well (WWW)

I identified the correct reference quantity, ratio, rate or multiplier and kept the units and proportional relationship clear.

Even Better If (EBI)

I will state the whole or reference quantity, show the multiplier or unit-rate step and check whether the result is sensible in context.

Stretch and deep challenge

Stretch: £1,000 grows 4% annually for three years. Find final value to the nearest penny.

Deep challenge: A price rises 20% then falls 20%. Prove it does not return to the starting price.