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Kindergarten Math · Chapter 6 · Lesson 2
Building Teen Numbers
Making any teen number you like.
10 problems · about 9 minutes · K.NBT.A.1
What this lesson teaches
The child builds a given teen number as ten ones and some more ones.
- Build a teen number by filling a ten first.
- Then add the extra ones.
- Write it as 10 plus the extras.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
4 problemsReview — Ten and Some More: 18 is 10 and how many?
Answer 8
Why Eight.
Review — Sums That Make Ten: 3 + ? = 10
Answer 7
Why Seven.
Review — Five and Some More: 8 is 5 and how many?
Answer 3
Why Three.
Review — Pairs That Make Ten: 4 and how many make 10?
Answer 6
Why Six.
Warm Up
Straightforward practice. Get the method working first.
3 problems10 + 5 = ?
Answer 15
Why Fifteen.
10 + 4 = ?
Answer 14
Why Fourteen.
10 + 8 = ?
Answer 18
Why Eighteen.
Build It Up
The same ideas with more to keep track of.
2 problems10 + ? = 13
Answer 3
Why Three extras.
10 + ? = 19
Answer 9
Why Nine extras.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
1 problemThe Sticker Sheet: A sheet of ten stickers and six loose ones. How many?
Answer 16
Why Sixteen.