Length Compare Direct

Watch: Watch whether the learner rejects cards whose lengths merely go down and chooses only a card with two equal positive drops. The decisive evidence is a checked DIAMOND selection after comparing 15 − 12 with 12 − 9.

Misread: A learner may treat the finished pieces as one tied bundle, tap a familiar shape, or answer with a length instead of choosing one whole card. STAR captures the likely mathematical misread: accepting any downward pattern without checking equal drops.

Curriculum: This task develops early functional reasoning with a constant positive additive change and an equal-start invariant. The scored skill is selecting the unique candidate with equal successive decreases and equal reconstructed starting values.