2.NBT.B.6 Grade 2 · Number and Operations in Base TenAdd up to four two-digit numbers using strategies based on place value and properties of operations.Common Core State Standards for Mathematics, as adopted in the Massachusetts Curriculum Framework for Mathematics (2017), Grade 2.
Play the game: Factors and Patternsfree, 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.
2.NBT.A.1Hundreds, tens and ones in a three-digit number2.NBT.A.2Count within 1000; skip-count by 5s, 10s and 100s2.NBT.A.3Read and write three-digit numbers: numerals, words, expanded form2.NBT.A.4Compare three-digit numbers with >, = and <2.NBT.B.5Add and subtract within 100 fluently using place value2.NBT.B.7Add and subtract within 1000; sometimes tens or hundreds are made or broken2.NBT.B.8Add or take 10 or 100 from a number between 100 and 900 in your head2.NBT.B.9Explain why addition and subtraction strategies workColorMyMath · 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.