Related Resources
The Place value Puzzle above is aligned (wholly or partially) with standard 1NBT04 taken from the Common Core Standards For Mathematics (see the extract below). The various resources listed below are aligned to the same standard.
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.