Misleading displays

Target: Reject a comparison that ignores a truncated axis.

Language target: Contrast “looks like” with the scale.

Likely miss: Students compare bar heights when the axis does not start at zero.

Ask: Where does the axis start?

If you see it: Check the scale before describing a bar as “twice as tall.”

Evidence to listen for: The student notices a truncated axis.

Next: Redraw the axis from zero if the picture is doing too much work.

Homework mark for this device

Until a teacher sets it here, family practice is optional. Stars are an incentive, not a grade. This setting is local. It is not a district roster.

unset optional required incentive

Observable student moves: names both quantities, uses the represented relationship, and revises after feedback. This companion is not a score.