Author note — to cover

Draw and interpret dual (side-by-side) and composite (stacked) bar charts comparing two or more categorical data sets; read a single component out of a stacked bar by subtraction, and make simple comparisons between groups. Percentage composite bars may appear. Single-set charts live on Bar charts. Both tiers. (S2)

• Fluency — direct questions on dual and composite bar charts, 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).