Reach for the Star

Number accuracy pathway · Optional extension

L056 · Allow 10–15 minutes for learners ready to move on. Answers are available after an attempt.

Stretch

Estimate 398×0.051 to one significant figure, then calculate exactly.

Reveal a worked check after attempting

Estimate 400×0.05=20; exact 20.298.

Deep challenge

A measurement rounds to 1.20 to two decimal places. State the interval and explain why 1.205 is excluded.

Reveal a worked check after attempting

1.195≤x<1.205; the upper endpoint rounds to 1.21.

Recall & Review: feedback and extension integration

Lesson L056: Number accuracy pathway

Objective: Select appropriate exact or approximate forms and explain accuracy.

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 selected an efficient numerical method, showed the key steps clearly and checked the sign, size or accuracy of my answer.

Even Better If (EBI)

I will make the place-value, sign or operation decision explicit and use estimation or an inverse calculation to check a fresh question.

Stretch and deep challenge

Stretch: Estimate 398×0.051 to one significant figure, then calculate exactly.

Deep challenge: A measurement rounds to 1.20 to two decimal places. State the interval and explain why 1.205 is excluded.