- (making 20) Beth had a pack of 20 pencils. The pencils were two different colors. Show all the combinations of pencils she could have that equal 20. Draw pictures and write equations to support your answer.
- If you don’t know 9 + 3, how can knowing 10 + 2 help you?
- If you don’t know 9 + 8, is there a doubles fact that can help you? How?
- (use of strategies) If you don’t know the sum of 8 + 5 (or any other fact), what are some good strategies you can use to help you figure out the answer? (finger counting isn’t appropriate, looking for mental math ideas) Have students think, pair, share ideas. Write all ideas on board for class to see.
- (making 10) Meghan wants to have 10 donuts in each box. How many more donuts does she need to put in each of the following boxes? A box with 9 donuts? A box with 8 donuts? A box with 3 donuts?
- (doubling) Sherry already has 4 erasers. Now her goal is to collect 20 in all. She got 4 more on Monday and 8 on Tuesday. How many does she have in all? How many more does she need to make her goal?
- (halving) Connie and Cheryl are twins. Connie’s hair is twice the length of Cheryl’s hair. Connie has decided that she wants to cut her hair to be the same length as her sister’s. Connie’s hair dresser measured her hair and it is 16 inches long. How long will the twins’ hair be?