3rd grade · Math · Unit 13 of 14
Halves & Fourths of an Inch
Measure to 1/4 inch
What your child practices
Measuring lengths to the nearest half and quarter inch, then reading the measurements from a table like a line plot.
Maine Learning Results learning standard: 3.MD.B.4 · measuring lengths to the nearest half and fourth of an inch and showing the data in a line plot
How we explain it
Children can open this short lesson before they practice.
- Each inch on the ruler is split into 4 equal parts.
- Count the whole inches, then the parts: 2/4 is the same as 1/2.
- A line plot shows how many objects have each length.
Example: A crayon starts at 0 and ends at the second mark after 2. How long is it? 2 whole inches. 2 marks is 2/4 = 1/2. Answer: 2 1/2 inches
Halves & Fourths of an Inch in Maine
In the Maine Learning Results, this is unit 13 of 14 in 3rd grade Math, after Two-Step Stories and before Scaled Graphs.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Maine Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
The dots mark the ends of a key on an inch ruler. How long is it?
- 2 1/2 in
- 4 1/2 in
- 3 1/2 in
- 3 1/4 in
3 1/2 in
Hint: Each inch is cut into 4 quarter inches. Count whole inches, then the parts.
Question 2
How many pencils are longer than 1 1/2 in?
Pencil lengths Length Pencils 1 in 2 1 1/2 in 6 2 in 1 2 1/2 in 4 - 6
- 5
- 3
- 4
5
Hint: Add the counts for the longer lengths only.
Question 3
Which length is the most common?
Pencil lengths Length Pencils 1 in 1 1 1/2 in 2 2 in 6 2 1/2 in 3 - 2 1/2 in
- 1 1/2 in
- 2 in
- 1 in
2 in
Hint: Look for the biggest count.
Question 4
How many pencils are 2 1/2 in long?
Pencil lengths Length Pencils 2 1/2 in 1 3 in 2 3 1/2 in 6 4 in 5 - 4
- 0
- 1
- 2
1
Hint: Find that length in the table and read across.
Question 5
Which is longer: 3/4 in or 2 1/4 in?
- 2 1/4 in
- 3/4 in
2 1/4 in
Hint: Compare the whole inches first, then the parts. 1/2 is the same as 2/4.
Question 6
How many pencils were measured in all?
Pencil lengths Length Pencils 2 in 5 2 1/2 in 2 3 in 6 3 1/2 in 3 - 16
- 18
- 15
- 14
16
Hint: Add the counts: 5 + 2 + 6 + 3.