Friday morning at afterschool in Markham often starts with contest-night energy. Someone opens a CCC-inspired warm-up, the room goes quiet, and the question is not “who finishes first” — it is who can name the useful state before they type.

A real classroom case: Library Stamp Card

We ran a CodeSky original warm-up inspired by CCC Junior: Library Stamp Card.

A library stamp card. Small stamps are worth 1 point, medium 2, large 3. You read three integers — small count, medium count, large count. If the weighted score is at least 12, print exactly happy. Otherwise print sad. The story prize is a free bookmark. The real prize is reading the question before writing a formula.

Sample A at exactly 12 must be happy. The classic trap is writing > instead of >=. Our 2026-09-25 Xiaohongshu note used this exact warm-up beat: read first, name the useful state, then test the inclusive boundary.

s = int(input())
m = int(input())
l = int(input())
score = 1 * s + 2 * m + 3 * l
if score >= 12:
    print("happy")
else:
    print("sad")

Why this still matters when AI can write code

Claims below are grounded in that teaching note — not an external product case with published accuracy metrics.

1. AI does not remove the need to read the question first. “Weighted score at least 12 → happy” is a different job from “print any word that looks friendly.” If a kid (or an AI prompt) muddles those, the next line that comes back solves the wrong problem.
2. The useful state is tiny on purpose. You only hold S, M, L → weighted score → compare to 12. That is abstraction: keep what the next decision needs, drop the rest.
3. The inclusive boundary is the algorithm. Sample A at exactly 12 must be happy; the trap is > instead of >=. Contest-style questions inspired by CCC Junior, CCC, BCC, and school contests reuse that move — kids who want to sit those register on their own; CodeSky is not an official contest program and is not affiliated with Waterloo or CEMC.
4. Languages are tools on a path, not the answer. Early work often uses Python so the steps stay readable; JavaScript when the same idea becomes something clickable on a screen; C++ later when speed and structure matter. Tools change; read → name useful state → test the boundary does not.

So AI’s ability to type code does not cancel a thinking-first start. It raises the value of kids who can decompose the inputs, name the weighted score, and check the inclusive edge before they ask a model to type.

Three steps kids can name

We practice the same shape on the bench:

1 · Read — question before formula

2 · Name — useful state is the weighted score

3 · Check — inclusive boundary so 12 is happy

• Decomposition — read → state → calc → print
• Abstraction — keep only weighted score and threshold 12
• Algorithms — weight 1/2/3, then if score >= 12 print happy else sad
• Pattern recognition — same inclusive-threshold trap in other weighted warm-ups and contest-style I/O

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Sources: CodeSky Xiaohongshu note pack 2026-09-25-图书馆集点卡 (Library Stamp Card; CCC-inspired warm-up; Python pathway; contest-style disclaimer). Inspired by CCC Junior — CodeSky original story and numbers.