Week 10 · Graphs and line plots
Wednesday
Halves and fourths of an inch
// Scaled graphs, rulers and line plots
⏱ about 15 min
Wednesday: Halves and fourths of an inch
Lizzy holds up a ruler and a pile of fallen leaves.
"This leaf is longer than 2 inches," she says.
"But it is shorter than 3 inches. What is its length?"
Bennie points to the small marks between the numbers.
"These marks cut each inch into fourths," he says.
"Count the fourths past 2, and you will know."
Learn it: read a ruler in fourths
An inch can be cut into 4 equal parts. Each part is one fourth of an inch.
Two fourths make one half. So the middle mark is a half inch.
Line up the end of the leaf with 0. Read where the other end stops.
The leaf ends 1 mark past 2 on this ruler.
So the leaf is 2 1/4 inches long.
MEASURE IN FOURTHS
- Read the question.
- Tap your answer.
A leaf starts at 0 and ends at the dot. How long is it?
A twig starts at 0 and ends at the dot. How long is it?
A seed pod starts at 0 and ends at the dot. How long is it?
A feather starts at 0 and ends at the dot. How long is it?
A pinecone scale starts at 0 and ends at the dot. How long is it?Learn it: read a ruler in halves
This ruler only shows halves. Each small mark is one half of an inch.
The dot is at 1 1/2 inches.
MEASURE IN HALVES
- Read the question.
- Tap your answer.
A stick starts at 0 and ends at the dot. How long is it?
A blade of grass starts at 0 and ends at the dot. How long is it?
A pebble starts at 0 and ends at the dot. How long is it?WHICH IS LONGER?
- Read the question.
- Tap your answer.
Which is longer: 1 3/4 inches or 2 1/4 inches?
Which is longer: 1 1/2 inches or 1 1/4 inches?
How many fourths of an inch make one half inch?
How many fourths of an inch make one whole inch?
MEASURE A LEAF
- Think about how Lizzy measures.
- Tap the steps in order.
1First
2Next
3Then
4Last
Picture the marks on a ruler.
| Sentence | True or false? |
|---|---|
| Two fourths of an inch make one half inch. | ? |
| We start measuring at 1 on the ruler. | ? |
| 2 1/4 inches is longer than 2 inches. | ? |
| 1/4 > 1/2 | ? |
WHY THIS EXERCISEWe line up the end with 0. One fourth is smaller than one half.
Try it
Find a ruler with inch marks.
Measure three small things, like a crayon, a spoon and a leaf.
Measure each one to the nearest fourth inch.
Write each length down. You will use them on Saturday.
Measure three small things, like a crayon, a spoon and a leaf.
Measure each one to the nearest fourth inch.
Write each length down. You will use them on Saturday.
Draw a leaf next to a ruler. Mark how long it is.
Nice measuring! Tomorrow Chris tells a story about a line plot.