3.NBT.A.2 Grade 3 · Number and Operations in Base TenFluently add and subtract within 1,000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.Common Core State Standards for Mathematics, as adopted in the Massachusetts Curriculum Framework for Mathematics (2017), Grade 3.
Play the game: Place by PlaceStep 54 of the ColorMyMath curriculum · free, no sign-up →Past nine, color tells you which place a digit lives in. A ten is a triangle of ten dots; the number of triangles is the tens digit, so 34 is three triangles and four loose green dots.
Every page is free and open — nothing to install, no account, and it works on a phone or a classroom board. Every number has its own color: 1 red, 2 orange, 3 yellow, 4 green, 5 blue, 6 purple, 7 brown, 8 pink, 9 cyan, and a number is that many colored dots.
Step 54Three-digit addition with hard facts — carryingStep 56Three-digit subtraction with hard facts — borrowingStep 68Three-digit addition with level one factsStep 69Three-digit subtraction with level one facts3.NBT.A.1Round to the nearest 10 or 1003.NBT.A.3Multiply a one-digit number by a multiple of ten: 9 × 80 is 72 tensColorMyMath · getridoftheteacher.com · every number has its own color, and a number is that many colored dots. Matching a game to a standard is a judgement call; the official text is at doe.mass.edu.