Thinking Summary · 1
MasteredEquation Logic: .
[Discovery] One non-trivial rectangle for 4 tiles is 2 × 2. What is 2 × 2?
1
Active StepWelcome to "Solo Donut Detector", a 4th Grade Primes mission at the Seedling (entry-level) level, staged in our bakery scenario. The mission opens with a hands-on prompt: "One non-trivial rectangle for 4 tiles is 2 × 2. What is 2 × 2?" You'll work with the numbers 4, 2, 1 and arrive at a final answer of 3 across 3 guided steps.
Behind the bakery story, this lesson is really about primes aligned to CCSS 4.OA.B.4. Determine whether a given whole number in the range 1-100 is prime or composite. The key strategy this mission asks you to internalise: Count distinct rectangles you can make.
A general pattern to watch for in 4th Grade primes — illustrated with example numbers below, which may differ from this lesson's: Stopping the divisor check too early or too late. You only need to check divisors up to √N. If none work, N is prime. If you get stuck on "Solo Donut Detector", 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 4 · Primes
Mission Progress
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Thinking Summary · 1
MasteredEquation Logic: .
[Discovery] One non-trivial rectangle for 4 tiles is 2 × 2. What is 2 × 2?
1
Active StepEverything you need to know about the Socratic experience.
One non-trivial rectangle for 4 tiles is 2 × 2. What is 2 × 2? Hint: Multiply 2 × 2.
How many factors does 4 have? (Count 1 and 4 too.) If you get stuck, the adaptive hint is: Composite numbers have more than 2 factors.
Seedling missions anchor the visual model with small, friendly numbers — ideal as the first attempt at this topic. Within 4th Grade Primes, expect numbers in the corresponding range.
Calling 1 a prime number. 1 has only ONE factor; primes have exactly TWO. The definition matters more than intuition.
Factors (Primes are the atoms of factor lists — every composite breaks into a unique prime product.). Open /grade-4/factors 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.
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.