1.NBT.4:
Number And Operations In Base Ten
Use Place Value Understanding And Properties Of Operations To Add And Subtract.
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. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
2.NBT.3:
Number And Operations In Base Ten
Understand Place Value.
Read and write numbers to 1000 using base-ten numerals, number names, and expanded form.
K.OA.1:
Operations And Algebraic Thinking
Understand Addition As Putting Together And Adding To, And Under- Stand Subtraction As Taking Apart And Taking From.
Represent addition and subtraction with objects, fingers, mental images, drawings2, sounds (e.g., claps), acting out situations, verbal explanations, expressions, or equations.
