Thinking Summary · 1
MasteredVisual Logic: 0 of 1 parts shaded.
[Discovery] There were 12 satellites. Shade the 4 that were recalled — the unshaded parts are what remains.
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Active StepWelcome to "Fuel Leak Stopper", a 1st Grade Subtraction mission at the Explorer (core) level, staged in our space exploration scenario. The mission opens with a hands-on prompt: "There were 12 satellites. Shade the 4 that were recalled — the unshaded parts are what remains." You'll work with the numbers 12, 4, 8 and arrive at a final answer of 4 across 3 guided steps.
Behind the space exploration story, this lesson is really about subtraction aligned to CCSS 1.OA.A.1. Understanding subtraction as taking from, taking apart, and comparing — within 20. The key strategy this mission asks you to internalise: Start at 12, count back 4.
A general pattern to watch for in 1st Grade subtraction — illustrated with example numbers below, which may differ from this lesson's: Forgetting subtraction is the undo of addition. Play fact-family games: give 3+2=5 and ask for the matching subtraction facts. If you get stuck on "Fuel Leak Stopper", the adaptive Socratic hints below escalate from a gentle nudge to a worked-out strategy — the same way a one-on-one tutor would coach you through it.
Grade 1 · Subtraction
Mission Progress
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Thinking Summary · 1
MasteredVisual Logic: 0 of 1 parts shaded.
[Discovery] There were 12 satellites. Shade the 4 that were recalled — the unshaded parts are what remains.
1
Active StepEverything you need to know about the Socratic experience.
There were 12 satellites. Shade the 4 that were recalled — the unshaded parts are what remains. Hint: Tap + until the bar has 12 parts, then tap 4 of them to mark them as recalled.
You know 4 + 8 = 12. So what is 12 − 8? If you get stuck, the adaptive hint is: One fact-family, three equations.
Explorer missions hit the core abstraction at typical numeric ranges — this is where conceptual mastery is built. Within 1st Grade Subtraction, expect numbers in the corresponding range.
Subtracting more than you have (e.g., 3 − 5). With physical objects, show it is impossible at Grade 1. Save negatives for later.
Comparing (Subtraction answers "how many more".). Open /grade-1/comparing to start that topic's missions.
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.
Inquiry-based learning starts with a question, not a formula — students explore, hypothesize, and verify before being told the rule. In Inquiry AI, every mission opens with a "Discovery" step (manipulate the model), then "Abstraction" (write the equation), then "Reflect" (apply to a new case). The procedure is never given upfront; learners derive it from their own observations.