A handout inspired by a great book called ‘One is a Snail; Ten is a Crab' by April Sayre. A lovely way to introduce tens & units or partitioning. Aligned with Common Core State Standards: 1.NBT.4, Number and Operations in Base Ten.
Tens & units handout
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.