Put parts together

Learning goal

Represent parts and a whole and connect joining to addition.

Before teaching

Can count the selected collections and recognize that the last count word gives the total.

Model

Place 2 counters in one part and 1 in the other. Move them into the whole: 3. Say “Two and one make three.” Connect the action to 2 + 1 = 3. Explain equals as the same amount, not a signal meaning “write an answer.”

Guide, then apply

Model the pupil stories with counters and drawings before writing equations. Separate the same whole into different parts. Include an empty part after zero is understood.

Interpret the response

Practice results: 2 + 1 = 3; 3 + 2 = 5; 4 + 0 = 4. If the child counts a moved counter again in both part and whole, physically separate the phases and recount the whole once.

Support

Use concrete action and spoken explanation without requiring equation writing. Point to each part and its role.

Extend when ready

Find different decompositions of a whole and explain what remains constant. Move toward K.OA.2 word problems within 10 when the smaller examples are understood.

Fresh check

Tell “There are 1 red cup and 3 blue cups. How many cups?” Ask for a model and explanation using a different arrangement.

Teacher plans PDF: page 13. Record exact support and revisit the idea later.