Cogito
Grade 1 Math · Chapter 7 · Lesson 8
One More, One Less, Ten More, Ten Less
Move in all four directions and say where you will land.
10 problems · about 12 minutes · 1.NBT.C.5, 1.NBT.A.1
What this lesson teaches
The child predicts the result of moving one more, one less, ten more, or ten less, then checks it on the chart.
- One more and one less move across the row.
- Ten more and ten less move down and up.
- Say your answer first, then check it.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
4 problemsReview — Ten More, Ten Less: What is ten more than 21?
Answer 31
Why 2 tens became 3 tens.
Review — Greater Than, Less Than, Equal To: What does < mean?
Answer Is less than.
Why < means is less than.
Review — Which Is More?: Which is greater, 30 or 27?
Answer 30
Why 30 has 3 tens. 27 has 2 tens.
Review — Many Ways to Show a Number: 2 tens and 16 ones is which number?
Answer 36
Why 20 and 16 is 36.
Warm Up
Straightforward practice. Get the method working first.
3 problemsTen less than 34 is?
Answer 24
Why 3 tens became 2 tens.
Which move goes across the row?
Answer One more.
Why One more is the next square along.
One less than 30 is?
Answer 29
Why Move back one square.
Build It Up
The same ideas with more to keep track of.
1 problemTen more than 19 is?
Answer 29
Why Move straight down.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
2 problemsOne more than 39 is?
Answer 40
Why The row ends there.
Steps on the Chart: Ana starts at 26. She goes ten more, then one less.
Answer 35 is where she lands
Why 26 to 36, then back one to 35.