Drag rhythmic values into up to 8 beat blocks per line to build a drum groove, or click a tile then click a block to place it — handy on a trackpad.

🎵 Grade 2 Lesson 20: Subtracting Across Hundreds — Subtract Within 1000 (2.NBT.B.7) mess around all you want, nothing here saves
90 BPM
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Grade 2, Lesson 20: Subtracting Across Hundreds

Math skill: Subtract Within 1000 (2.NBT.B.7)

How the beat teaches it: Every slot subtracts from a round hundred — build what's left across hundreds, tens, and ones.

This is lesson 20 of 24 in RockBlocks Math, Grade 2, a free course where every lesson turns a math idea into something you can count, hear, and play. The previous lesson, Adding Within 200,” covered add Within 1000 (2.NBT.B.7). Next is Lesson 21, Telling Time to the Half Hour.”

Every slot above (A, B, C, D) is its own question, and it’s a real, blank RockBlocks beat the whole time — the same drag-and-drop tiles, kit, tempo, sheet music, and drummer view as anywhere else on the site. Tap ❓ Questionin the corner to read the current slot’s problem, build your answer right in the grid, then tap ✓ Check Answerto grade it. Once you’re done, keep going: expand the beat, drop it into a Stack, or save a copy to your own page — nothing here overwrites the lesson itself, so every visitor still starts from the same blank slots.