Author note — to cover

Justify which average suits a context: mode for categorical data, median when extremes or skew distort, mean when every value should count, with one advantage and drawback of each. Question types: choose and defend in context, or criticise a stated choice. Calculating each average lives on its own sibling page. Both tiers. (S4)

• Fluency — direct questions on choosing which average to use, 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).