Common Core: Number & Operations in Base Ten
1.NBT.C4
Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. … Read More “1.NBT.C4”
October 1, 20181.NBT.C5
Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
October 1, 2018K.NBT.A1
Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decomposition by a drawing or equation (such as 18 = 10 + 8); understand that these numbers are composed of ten ones and one, two, three, four, five, six, … Read More “K.NBT.A1”
October 1, 2018