Lesson 6: The Doubles Now that you have memorized the tens, next up are the Doubles. The Doubles are easy to memorize because both addends are exactly the same. Also, there is a pattern in the sums that make them easy to remember. Part 1: Add to find each Doubles fact. Notice that the last digit in the sums follow the pattern: 2 – 4 – 6 – 8 – 0. Part 2: Count by two and shade in the Doubles in the chart below. The first two have been done for you.