Using Materials

Problem: The farmer has 28 cows. She buys some more cows at the market. Now she  has 33 cows. How many cows did she buy?

Record 28 + ? = 33 on the board. Tell the students to model 28 cows with 2 tens animal strip and an 8 animal strip. Tell them you want them to make a complete ten by  modelling 30 animals. Before they put a strip on students should predict that they need a 2; let them check by doing this. Now ask them to predict what strip they need to  reach 33 and check it. Ask how many animals were added on altogether. Record 28 + 5  = 33 on the board

Examples. Word stories and recording for: 7 + ? = 13, 26 + ?  = 31, 8 + ? = 13, 18 + ? = 23, 25 + ? = 32, 17 + ? = 24

Using Imaging

Shielding and Imaging Only:
Examples. Word stories and recording for:

17 + ? = 23, 16 + ? = 25, 28 + ? = 35, 14 + ? = 23, 35 + ? = 41, 23 + ? = 31 …

Using Number Properties

Examples. Word stories and recording for:  77 + ?  =83,  56 + ? = 65, 68 + ?  = 75, 54 +? = 53, 65 +? 71, 22 + ? = 31 ...