Thinking Summary · 1
MasteredVisual Logic: 0 of 1 parts shaded.
[Discovery] There were 9 donuts. Shade the 3 that were eaten — the unshaded parts are what remains.
1
Active StepWelcome to "Muffin Sale Tracker", a 1st Grade Subtraction mission at the Seedling (entry-level) level, staged in our bakery scenario. The mission opens with a hands-on prompt: "There were 9 donuts. Shade the 3 that were eaten — the unshaded parts are what remains." You'll work with the numbers 9, 3, 6 and arrive at a final answer of 3 across 3 guided steps.
Behind the bakery 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 9, count back 3.
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 "Muffin Sale Tracker", 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 9 donuts. Shade the 3 that were eaten — the unshaded parts are what remains.
1
Active StepEverything you need to know about the Socratic experience.
There were 9 donuts. Shade the 3 that were eaten — the unshaded parts are what remains. Hint: Tap + until the bar has 9 parts, then tap 3 of them to mark them as eaten.
You know 3 + 6 = 9. So what is 9 − 6? If you get stuck, the adaptive hint is: One fact-family, three equations.
Seedling missions anchor the visual model with small, friendly numbers — ideal as the first attempt at this topic. 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.
Addition (Partner operation — same fact-family.). Open /grade-1/addition to start that topic's missions.
Research on "productive struggle" shows that 20–60 seconds of focused effort BEFORE help dramatically improves long-term retention — the brain encodes the strategy more deeply. Inquiry AI's hint timing is calibrated to this window: short enough to prevent frustration, long enough to lock in the learning. Parents can adjust the threshold in settings if a learner needs faster scaffolding.
Yes. Every mission, handbook page, and topic hub is mapped to a specific CCSS code (visible in the page header). The curriculum follows the CCSS coherence map: Grade 1 number sense → Grade 3 multiplicative thinking → Grade 6 ratio reasoning, with each grade building strictly on the prior year's foundations.