Best Buy Problems

• Identify best buy problems accurately in a familiar context.

  Activities — Modelled example on the board · Paired talk task · Mini whiteboard check

  Assessment — Exit ticket of four short items

• Identify best buy problems independently in an unfamiliar context.

  Activities — Independent worksheet · Card sort · Concept-check quiz

  Assessment — Marked worksheet with a marking scheme

• Explain best buy problems accurately in a familiar context.

  Activities — Modelled example on the board · Paired talk task · Mini whiteboard check

  Assessment — Exit ticket of four short items

• Explain best buy problems independently in an unfamiliar context.

  Activities — Independent worksheet · Card sort · Concept-check quiz

  Assessment — Marked worksheet with a marking scheme

• Explain the reasoning behind best buy problems using correct vocabulary.

  Activities — Talk-through with a partner · Write a model answer · AI Tutor Socratic session

  Assessment — Extended written response, levelled

• Calculate best buy problems accurately in a familiar context.

  Activities — Modelled example on the board · Paired talk task · Mini whiteboard check

  Assessment — Exit ticket of four short items

• Calculate best buy problems independently in an unfamiliar context.

  Activities — Independent worksheet · Card sort · Concept-check quiz

  Assessment — Marked worksheet with a marking scheme

• Compare best buy problems accurately in a familiar context.

  Activities — Modelled example on the board · Paired talk task · Mini whiteboard check

  Assessment — Exit ticket of four short items

• Compare best buy problems independently in an unfamiliar context.

  Activities — Independent worksheet · Card sort · Concept-check quiz

  Assessment — Marked worksheet with a marking scheme

• Explain the reasoning behind best buy problems using correct vocabulary.

  Activities — Talk-through with a partner · Write a model answer · AI Tutor Socratic session

  Assessment — Extended written response, levelled

• Scale FactorsUnit
• Inverse ProportionUnit
• RatioStrand

• Direct Proportion
• Inverse Proportion
• Scale Factors
• Counting

Students treat best buy problems as a rule to memorise rather than a relationship to understand.

Correction — Anchor the rule in a visual model first, then abstract it — the model is the explanation.

Learners apply the correct method to best buy problems but ignore the context or units.

Correction — Require an answer sentence with units on every applied question.