Welcome to "Donut Box Filler", a 2nd Grade Addition mission at the Seedling (entry-level) level, staged in our bakery scenario. The mission opens with a hands-on prompt: "21 cookies already loaded, and 34 more on the way. Bundle every 10 into one tray. Build 2 trays for the first batch and 3 for the second — each holding 10." You'll work with the numbers 21, 34, 10 and arrive at a final answer of 65 across 3 guided steps.
Behind the bakery story, this lesson is really about addition aligned to CCSS 2.NBT.B.5. Fluently add within 100 using strategies based on place value, properties of operations, and the relationship between addition and subtraction. The key strategy this mission asks you to internalise: Tens: 2 + 3. Ones: 1 + 4. Combine with any trade.
A general pattern to watch for in 2nd Grade addition — illustrated with example numbers below, which may differ from this lesson's: Writing the full ten-sum in the ones column (e.g., writing 10 under 4 + 6). Only the ones digit of the sum stays in the ones column. The ten moves up to the tens column as 1. If you get stuck on "Donut Box Filler", 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.
