Welcome to "Donut Tray Skip", a Grade 2 Skip Counting by 5, 10, 100 mission at the Challenger stretch problem level, staged in a bakery scenario. The mission opens with a hands-on prompt: "Start at 0 and skip-count by 100. Place 400 on the number line." Students work with the numbers 0, 100, 400 and reach a final answer of 4 across 3 guided steps.
Behind the story, this lesson builds skip counting by 5, 10, 100 understanding aligned to CCSS 2.NBT.A.2. The key strategy is: 400 + 100 = 500.
A common misconception this page surfaces is: Adding 1 instead of the chosen step (e.g. counting by 5 → 5, 6, 7…). State the rule first: "every jump = +5." Then chant the sequence so the rule sticks before the next number. The adaptive Socratic hints move from a small nudge to a fuller strategy, keeping the reasoning visible for students, parents, and teachers.
Grade 2 · Skip Counting by 5, 10, 100
Mission Progress
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Thinking Summary · 1
Mastered[object Object]
[Discovery] Start at 0 and skip-count by 100. Place 400 on the number line.
1
Active StepPlace the marker on 400.
2nd Grade Skip Counting by 5, 10, 100 challenger-1 representative practice page for students who need a crawlable, worked entry point into the topic without exposing every near-duplicate long-tail mission.
This challenger · stretch problem mission uses a number line to move from the story to a precise skip counting by 5, 10, 100 idea. Work through the prompts in order: notice the structure first, name the quantities, then check whether the final answer fits the original situation.
Common wrong turn: 0 is where we BEGIN. We need to land on 400.
Common wrong turn: That's the PREVIOUS number, not the next.
Common wrong turn: Off by one — the start tick (0) is NOT a jump, it's the launching pad.
In 2nd Grade Skip Counting by 5, 10, 100, students need to connect the story, the model, and the symbolic answer. The core move here is: 400 + 100 = 500. A useful check is to ask whether the answer avoids this pitfall: Adding 1 instead of the chosen step (e.g. counting by 5 → 5, 6, 7…). State the rule first: "every jump = +5." Then chant the sequence so the rule sticks before the next number.
Everything you need to know about the Socratic experience.
Start at 0 and skip-count by 100. Place 400 on the number line. Hint: Each tick is +100. Count: 0, 100, 200, …
How many jumps of 100 are needed to go from 0 to 400? If you get stuck, the adaptive hint is: (400 − 0) ÷ 100 = 4.
Challenger missions push beyond CCSS expectations with edge cases that surface deeper misconceptions. Within Grade 2 Skip Counting by 5, 10, 100, expect numbers in the corresponding range.
Adding 1 instead of the chosen step (e.g. counting by 5 → 5, 6, 7…). State the rule first: "every jump = +5." Then chant the sequence so the rule sticks before the next number.
Place Value to 1000 (Skip counting by 100 makes the hundreds column tangible.) Open /grade-2/placevalue to start that topic's missions.
C-P-A is the Singapore Math sequence proven to deepen number sense: first manipulate physical objects (Concrete), then draw pictures of them (Pictorial), and only then write equations (Abstract). Inquiry AI structures every mission as exactly these three steps — a manipulative, a picture/grid model, and finally the equation. Skipping straight to symbols is the #1 cause of math anxiety; the platform refuses to do it.
Pure discovery is inefficient — kids hit a wall and quit. Guided Discovery scaffolds the path: a careful sequence of questions, models, and adaptive hints leads the learner toward the insight without revealing it. Inquiry AI's hint system fires automatically after ~15s of hesitation or on the first mistake, escalating from a Socratic nudge to a worked example only when needed. Mistakes are diagnosed via "misconception keys" so the hint matches the actual wrong-thinking pattern.
