This two-page download helps students develop relational thinking and use what they know to learn near doubles sums to twenty. They may also notice the relationship between the actual doubles, such as they are all even numbers and saying the sums in order from least to greatest is counting by twos. With or without a little questioning, they may be able to explain why these two things are true. I recommend printing on card stock, either two separate pages or both sides of one page. It is intended to be used with dry-erase markers, so it can either be laminated or placed in a page protector.