Walk the equal spaces between 0 and 1 to connect a fraction denominator to distance, not tick marks.
Listen for the idea
The denominator counts equal intervals in one unit; the numerator counts intervals traveled from zero.
Count intervals between 0 and 1 without counting the starting mark.
Place a fraction using equal-length steps from zero.
Materials: Paper and ruler; Pencil.
A 12-minute route
2 minutes: Try the three diagnostic questions. Ask for a brief explanation.
3 minutes: Teach one worked example that addresses the difficulty.
5 minutes: Choose three practice tasks and discuss the reasoning.
2 minutes: Give one transfer task independently and decide the next step.
The second worked example, three unused practice tasks, and remaining transfer task are available for a follow-up session. Allow more time if the group needs to build the models.
Teaching move: Have the student touch a space while saying each count. Put a small arc over every interval and keep the mark at zero visibly separate from the first step.
Use the answer notes to interpret what you hear. Choose a response for each question to get a suggested teaching step. These choices describe this brief check and are not a mastery score.
1 A number line from 0 to 1 has marks at 0, 1/4, 2/4, 3/4, and 1. How many equal intervals does it have?
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: 4 equal intervals, although it has 5 marks.
Listen for this difficulty: Counting endpoint marks as fractional parts.
Try this response: Slide a finger across each gap, starting the first count after leaving zero.
Look for:
Counts 4 spaces.
Distinguishes 5 marks from 4 intervals.
2 Starting at 0 on a line divided into sixths, a student counts the zero mark as “one” and labels the next mark 2/6. Repair the label.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: The next mark is 1/6 because only one sixth-length interval has been traveled.
Listen for this difficulty: Including zero as a traveled step.
Try this response: Ask what distance has been traveled before taking the first step.
Look for:
Labels the next mark 1/6.
Explains zero is the starting position.
3 A line from 0 to 1 has three gaps of different lengths. Can its marks be labeled 0, 1/3, 2/3, 1 in order? Explain.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: No. Thirds require three equal-length intervals.
Listen for this difficulty: Treating any three consecutive gaps as thirds.
Try this response: Measure or copy the first gap to check whether it fits the other two.
Look for:
Rejects the thirds labeling.
Requires equal interval lengths.
2 · Model together
Two worked examples
Use one now. Ask the learner to explain each step before revealing the next part of your drawing.
1 Draw a line from 0 to 1 and locate 3/4.
Mark and label 0 and 1 first.
Partition their distance into four equal intervals; this needs five marks including both ends.
Count three intervals from 0.
Label the endpoint of the third interval 3/4.
Result: 3/4 is the endpoint after three fourth-length steps from zero.
Teaching notes
Listen for this difficulty: Placing 3/4 at the third mark when zero is counted as mark one.
Try this response: Draw three travel arcs and read their endpoints: 1/4, 2/4, 3/4.
Look for:
Uses four equal intervals in the unit.
Locates the endpoint after three steps.
2 A line from 0 to 1 has seven equally spaced marks including its endpoints. Name the point two intervals from 0.
Seven marks create six gaps.
The distance between neighboring marks is 1/6.
Travel two of those intervals from zero.
Name the endpoint 2/6; two sixths also make one third.
Result: 2/6, equivalent to 1/3.
Teaching notes
Listen for this difficulty: Using seven marks to claim sevenths.
Try this response: Underline the six gaps before writing a denominator.
Look for:
Uses denominator 6.
Counts two intervals rather than two marks.
3 · Guided practice
Choose three tasks
Mix a calculation or drawing with an explanation or error repair. Keep the other tasks for another short session.
1 Draw a unit line with 3 equal intervals. How many marks are needed when both 0 and 1 are included?
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: 4 marks.
Listen for this difficulty: Assuming the mark count equals the interval count.
Try this response: Start with the zero mark and add one endpoint for each of three steps.
Look for:
Draws three equal gaps.
Counts four marks including endpoints.
2 On a unit line split into eighths, what fraction is reached after five equal steps from 0?
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: 5/8.
Listen for this difficulty: Swapping the traveled steps and unit partition counts.
Try this response: Name the step size first, then count five copies.
Look for:
Names eighths as the step size.
Labels 5/8.
3 A line has labels 0, A, B, C, 1, all equally spaced. Name B.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: 2/4, or 1/2.
Listen for this difficulty: Using five letters or labels as the denominator.
Try this response: Count the four gaps and mark the two that reach B.
Look for:
Identifies four equal intervals.
Names B as 2/4 or 1/2.
4 A student draws marks at 0 cm, 2 cm, 5 cm, and 6 cm and labels them 0, 1/3, 2/3, 1. Repair the positions of the two interior marks.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: Place the interior marks at 2 cm and 4 cm, making three equal 2 cm intervals.
Listen for this difficulty: Accepting unequal spacing when labels look correct.
Try this response: Compare all three gap lengths to the first gap.
Look for:
Moves the second interior mark to 4 cm.
Checks three equal 2 cm intervals.
5 Draw 2/3 on a line from 0 to 1. Add an arc over each interval you travel.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: A unit split into three equal intervals with two arcs ending at 2/3.
Listen for this difficulty: Drawing two marks instead of traveling two intervals.
Try this response: Ask the learner to describe the length of each arc.
Look for:
Shows thirds with equal spacing.
Uses two arcs from zero ending at 2/3.
6 A point is three steps from zero on a unit line. Is that enough information to name its fraction? Explain.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: No. The length of each step, or the number of equal steps in one whole unit, is also needed.
Listen for this difficulty: Using the numerator without a defined unit fraction.
Try this response: Compare three steps on a fourths line with three steps on an eighths line.
Look for:
Recognizes missing step size.
Explains that different unit partitions give different fractions.
4 · Independent transfer
Try a fresh situation
Choose one task without coaching. Check the explanation against both criteria in its teaching notes; use the other task for a later check.
1 A 12 cm line represents 0 to 1. Mark 5/6 and explain the difference between the number of marks and the number of intervals.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: 5/6 is 10 cm from 0. Six 2 cm intervals require seven marks including the endpoints.
Listen for this difficulty: Using endpoint count to determine the denominator.
Try this response: Build the line with six 2 cm steps, then count endpoints separately.
Look for:
Locates 5/6 at 10 cm.
Distinguishes six intervals from seven marks.
2 A robot moves from 0 to 1 in three equal jumps. It stops after jump two. A friend calls the point 3/4 because there are four marks. Write a correction.
Explain with a drawing, objects, or words.
Answer & teaching response
Answer or sample response: The robot stops at 2/3. Three equal jumps make the unit, and two jumps have been completed.
Listen for this difficulty: Mixing the count of all marks with the count of reached marks.
Try this response: Have the student name what each number in 2/3 counts.
Look for:
Corrects the location to 2/3.
Explains numerator as traveled jumps and denominator as jumps per unit.
What to do next
If the explanation holds: Continue when the student can justify both the denominator and the location without counting zero as a step.
If the difficulty remains: Lay four equal paper segments between 0 and 1. Trace the lengths, then remove the segments and retain their endpoints.
Standards: 3.NF.A.2.a, 3.NF.A.2.b. Grade 3 alignment describes the mathematical work in this pack.
The tasks, worked examples, and teacher responses are original Fraction Classroom materials, version 2.0.0. The teaching approach draws on noticing the unit, moving between representations, and responding to student reasoning in the linked Illustrative Mathematics lesson. Its text and exercises are not reproduced here.