This unit focuses on number bonds to 5 in the context of a part-whole model. This is the first time children have been introduced to the part-whole model and the idea that there are a limited number of bonds to a given number (5 in this case) and that if 2 and 3, for example, make 5, then so must 3 and 2. This is the basis of understanding addition and subtraction.
When using the vocabulary whole, children may confuse the meaning with the word hole, as in ‘a hole in the ground’. Ask:
• What is the ‘whole’ of the class? [All of us.] What are the parts of the class? [Each child or group of children, such as those who walk to school and those who do not or the 4-year-olds and 5-year-olds.]
When counting the parts in a part-whole model to find the whole, children may include the whole in the count. Encourage children to count out loud, using concrete manipulatives such as cubes or wooden blocks to represent the whole and parts. Ask:
• Where is the whole on this model? Where are the parts? How many parts make this whole? Do you need to count the whole as well?