These are the rest of the Addition facts that the Common Core suggests that students be able to compute mentally such as 11 + 7, 4 + 13, and 16 + 3. These obviously build on the basic single digit facts such as 1 + 7, 4 + 3, and 6 + 3. Students should find these fairly easy to master but they still need some practice to commit them to memory. LOOK OUT! Because all the answers are two digits, the number of problems students can be expected to answer will go down! You must give the special Add to 20 Writing Speed Test to set new lower goals for your students. To the left you can see the sequence of facts that will be learned in the Add to 20 program. Otherwise the program is exactly the same as the basic Addition Rocket Math program and uses the same forms–that can be found in the forms and information drawer.