Welcome to "Sprinkle Grain Sorter", a 1st Grade Placevalue mission at the Challenger (stretch) level, staged in our bakery scenario. The mission opens with a hands-on prompt: "Build 71 with base-ten blocks. Use 7 ten-rods and 1 unit." You'll work with the numbers 71, 7, 1 and arrive at a final answer of 80 across 3 guided steps.
Behind the bakery story, this lesson is really about placevalue aligned to CCSS 1.NBT.B.2. Understanding that two-digit numbers are built from tens and ones — the power of grouping by 10. The key strategy this mission asks you to internalise: Position gives value: tens digit × 10.
A general pattern to watch for in 1st Grade placevalue — illustrated with example numbers below, which may differ from this lesson's: Writing 24 as "204" (thinking 2 tens + 4 ones = "204"). The tens digit already *counts* tens. You don't add a zero — position does the work. If you get stuck on "Sprinkle Grain Sorter", 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 · Placevalue
Mission Progress
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Thinking Summary · 1
Mastered[object Object]
[Discovery] Build 71 with base-ten blocks. Use 7 ten-rods and 1 unit.
1
Active StepBuild the number 71 using flats, rods, and units.
Everything you need to know about the Socratic experience.
Build 71 with base-ten blocks. Use 7 ten-rods and 1 unit. Hint: Add 7 rods (each = 10) and 1 unit (each = 1).
If we add 9 more ONES to 71, what number do we make? If you get stuck, the adaptive hint is: After rolling over, the tens digit goes up by 1, ones digit goes to 0.
Challenger missions push beyond CCSS expectations with edge cases that surface deeper misconceptions. Within 1st Grade Placevalue, expect numbers in the corresponding range.
Confusing which place is tens vs ones. Right-most column is ALWAYS ones. Move left: ones, tens, hundreds. Point while saying it.
Comparing (Two-digit comparison rests entirely on tens-vs-ones logic.). Open /grade-1/comparing to start that topic's missions.
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.
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.
