Cogito
Grade 2 Math · Chapter 3 · Lesson 3
Skip-Counting by 5s, 10s, and 100s
Count in jumps instead of one at a time.
10 problems · about 12 minutes · 2.NBT.A.2
What this lesson teaches
The child skip-counts by 5s, 10s, and 100s within 1,000 from any starting point.
- Skip counting uses equal jumps.
- By 5s, by 10s, or by 100s.
- You can start from any number.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
2 problemsReview — Building Numbers to 1,000: 6 hundreds, 0 tens and 3 ones is which number?
Answer 603
Why 603 has no tens.
Review — A New Unit: The Hundred: How many tens are in one hundred?
Answer 10
Why Ten tens make a hundred.
Warm Up
Straightforward practice. Get the method working first.
4 problemsCounting by 5s: 40, 45, ?
Answer 50
Why 45 and 5 more is 50.
When you count by hundreds, which digit changes?
Answer The hundreds digit.
Why Only the hundreds digit moves.
Counting by 5s: 25, 30, 35, ?
Answer 40
Why Add 5.
Counting by 10s: 460, 470, 480, ?
Answer 490
Why Add one ten.
Build It Up
The same ideas with more to keep track of.
2 problemsCounting by 100s: 130, 230, 330, ?
Answer 430
Why Only the hundreds digit changes.
Counting by 10s: 390, ?
Answer 400
Why Nine tens and one more ten.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
2 problemsCounting Money: Leo counts 5p coins: 5, 10, 15. What comes next?
Answer 20
Why 15 and 5 more is 20.
Stacks of Hundreds: Ana counts by hundreds: 200, 300, 400. What comes next?
Answer 500
Why 400 and 100 more is 500.