Keep students engaged with the fastest and easiest way to learn how to mentally add tens by a one-digit number using step-by-step animations. These step-by-step animated worked examples make it substantially easier for students to recognize patterns and understand the steps involved when mentally adding tens by any one-digit number. Students will be able to instantly pick up this pivotal fundamental skill. This content is aligned with Common Core State Standard 1.NBT.C.4. It is perfect for