Cogito
Grade 2 Math · Chapter 2 · Lesson 3
Inches and Feet
Another pair of units, used the same way.
10 problems · about 11 minutes · 2.MD.A.1
What this lesson teaches
The child measures in inches and knows that 12 inches make 1 foot.
- Inches and feet are another pair of length units.
- One foot is 12 inches.
- Measuring works the same way in any unit.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
3 problemsReview — Centimetres and Metres: How many centimetres are in a metre?
Answer 100
Why 1 metre = 100 centimetres.
Review — Measuring in Centimetres: Where should one end of the object go?
Answer On the 0.
Why Starting at 0 makes the far end read the length directly.
Review — Two-Step Word Problems: 9 sweets. 5 more given. 6 eaten. How many are left?
Answer 8
Why 9 + 5 = 14, and 14 − 6 = 8.
Warm Up
Straightforward practice. Get the method working first.
3 problemsHow many inches are in a foot?
Answer 12
Why 1 foot = 12 inches.
Does measuring in inches work differently from centimetres?
Answer No. Start at 0 and read the far end.
Why The method is identical. Only the unit is different.
How many inches make one foot?
Answer 12
Why A dozen.
Build It Up
The same ideas with more to keep track of.
1 problemAn object goes from 0 to 6 inches. How long is it?
Answer 6
Why It starts at 0.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
3 problemsAn object goes from 2 to 9 inches. How long is it?
Answer 7
Why 9 take away 2.
A Foot Ruler: A ruler is one foot long. How many inches is that?
Answer 12 inches
Why 1 foot = 12 inches.
The Book: A book starts at 0 and its edge lands on 9. How long is the book?
Answer 9 inches
Why It is 9 inches long.