Common Core math · 2nd grade
Add and subtract within 100 fluently using place value.
2.NBT.B.5 is part of the Common Core State Standards for Mathematics. Big Number Bakery practices it. Standards vary by state, so check with your kid’s teacher for the exact match.
Big Number Bakery: Two-digit numbers are boxes of 10 cupcakes plus loose ones. Adding past 9 ones packs a new box, and subtracting can mean opening one. A tens-and-ones column sheet shows the worked steps, so carrying and borrowing make sense before they're a rule.