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.
Alabama Course of Study content standard: 3.17 · 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 Alabama
In the Alabama Course of Study, 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.
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
Which length is the most common?
Pencil lengths Length Pencils 2 1/2 in 3 3 in 5 3 1/2 in 4 4 in 1 - 3 in
- 2 1/2 in
- 4 in
- 3 1/2 in
3 in
Hint: Look for the biggest count.
Question 2
How many pencils are longer than 1 1/2 in?
Pencil lengths Length Pencils 1 in 6 1 1/2 in 3 2 in 4 2 1/2 in 5 - 6
- 9
- 7
- 12
9
Hint: Add the counts for the longer lengths only.
Question 3
Which is longer: 2 3/4 in or 1 3/4 in?
- 2 3/4 in
- 1 3/4 in
2 3/4 in
Hint: Compare the whole inches first, then the parts. 1/2 is the same as 2/4.
Question 4
How many pencils were measured in all?
Pencil lengths Length Pencils 1 in 5 1 1/2 in 2 2 in 1 2 1/2 in 4 - 9
- 11
- 10
- 12
12
Hint: Add the counts: 5 + 2 + 1 + 4.
Question 5
How many pencils are 1 1/2 in long?
Pencil lengths Length Pencils 1 in 3 1 1/2 in 6 2 in 5 2 1/2 in 1 - 5
- 7
- 9
- 6
6
Hint: Find that length in the table and read across.
Question 6
The dots mark the ends of a crayon on an inch ruler. How long is it?
- 4 in
- 3 in
- 4 3/4 in
- 5 in
4 in
Hint: Each inch is cut into 4 quarter inches. Count whole inches, then the parts.