Fraction Classroom

Grade 3 / Unit fractions & equal parts

Fraction Museum

Create and critique exhibits showing equal fraction values.

45 min · Grade 3 · Paper and pencils

Teaching companion · Version 2.0.0

Diagnose, reteach, and choose the next step

Audit fraction exhibits for equal parts, accurate labels, and equivalent values.

The original lesson PDFs remain version 1.0.0. This supplement adds diagnostic probes, teaching responses, and question-specific rubrics. Use the supplement below for the updated guidance.

Begin with two short probes

Ask for an explanation or drawing before choosing a response. A wrong answer alone does not identify its cause.

  1. One exhibit shades one of two equal parts; another shades three of six equal parts on an identical whole. Do they show the same amount?

    Answer and teaching response for d1

    Look for: Yes. Both show one half of the same-sized whole.

    If you observe: Says three selected pieces must exceed one selected piece.

    Respond: Align the shaded endpoints and split each half into three sixths to connect the counts.

  2. An exhibit labeled 2/3 shows two of four equal parts shaded. What repair would make it accurate?

    Answer and teaching response for d2

    Look for: Change the label to 2/4 (or 1/2), or repartition into thirds and shade two.

    If you observe: Keeps the label because two pieces are shaded.

    Respond: Ask the learner to name one piece from the whole’s partition before counting selected pieces.

Curate one valid exhibit and one repair

  1. Prepare a valid half exhibit and a mislabeled two-of-four exhibit.
  2. Check the whole, equality of areas, total count, and selected count in that order.
  3. Pair equivalent exhibits by aligned endpoints, then write a precise curator note explaining one repair.

Check independently: Would an uneven six-part picture be ready to display as 3/6 just because three pieces are shaded?

Answer to the reteaching check

No. First verify or repair equal part areas; count alone does not establish sixths.

Use the equivalent factors short intervention if the difficulty persists. Return to this check before repeating the exit ticket.

Read both exit responses

  • e1 gives = for 1/2 compared with 3/6.
  • e2 describes a concrete model check and what evidence would pass it, using its rubric.

Ready to continue

e1 meets its criterion: e1 gives = for 1/2 compared with 3/6. e2 also meets its criterion: e2 describes a concrete model check and what evidence would pass it, using its rubric.

Continue to the linked next lesson. Explain equivalent exhibits by repartitioning the same fixed whole.

Next lesson: Equivalent Strip Lab

Revisit the calculation or model

e1 does not yet meet this criterion: e1 gives = for 1/2 compared with 3/6.

Ask the learner to explain the attempt, then use the matching diagnostic probe to identify the difficulty. Work through the focused reteach below and its check. Use the linked short intervention if the difficulty persists; retry e1 and e2 before moving on.

Open the linked short intervention

Strengthen the explanation

e1 meets its criterion, but e2 does not yet show this evidence: e2 describes a concrete model check and what evidence would pass it, using its rubric.

Present the mislabeled exhibit again. Ask the learner to apply the proposed e2 check and say exactly what would need repair.

Open the linked short intervention
Question-by-question misconception guide and open-response criteria

Use these as follow-up prompts, then examine the learner’s model or explanation. Open responses may differ from the sample while satisfying the criteria.

c1: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 2 equal parts; 1 parts are shaded altogether.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

c2: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 4 equal parts; 2 parts are shaded altogether.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

c3: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 6 equal parts; 3 parts are shaded altogether.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

c4: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 8 equal parts; 4 parts are shaded altogether.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

c5: Compare 1/2 and 2/4. Choose <, =, or >. The wholes are the same size.

Watch for: Changes one part of a fraction without scaling numerator and denominator by the same factor.

Try: Shade 2/3 of a fixed strip and split each third into two equal parts. Count four shaded sixths out of six. Write ×2 on both arrows and check that the shaded endpoint did not move.

c6: Compare 2/3 and 4/6. Choose <, =, or >. The wholes are the same size.

Watch for: Changes one part of a fraction without scaling numerator and denominator by the same factor.

Try: Shade 2/3 of a fixed strip and split each third into two equal parts. Count four shaded sixths out of six. Write ×2 on both arrows and check that the shaded endpoint did not move.

c7: Compare 3/4 and 6/8. Choose <, =, or >. The wholes are the same size.

Watch for: Changes one part of a fraction without scaling numerator and denominator by the same factor.

Try: Shade 2/3 of a fixed strip and split each third into two equal parts. Count four shaded sixths out of six. Write ×2 on both arrows and check that the shaded endpoint did not move.

c8: Compare 2/2 and 3/3. Choose <, =, or >. The wholes are the same size.

Watch for: Does not recognize that b copies of 1/b make one whole.

Try: Fill one outlined whole with b equal pieces and label the completed whole b/b. Exchange the complete collection for a card labeled 1; do the exchange again with a different partition.

s1: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 2 equal parts; 1 parts are shaded altogether.

Watch for: Treats the denominator as a count of selected pieces instead of the number of equal parts in one whole.

Try: Outline one whole first. Count all the equal pieces that fill it, label one piece 1/b, then repeat that piece until the whole is covered with no gaps.

s2: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 3 equal parts; 1 parts are shaded altogether.

Watch for: Treats the denominator as a count of selected pieces instead of the number of equal parts in one whole.

Try: Outline one whole first. Count all the equal pieces that fill it, label one piece 1/b, then repeat that piece until the whole is covered with no gaps.

s3: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 4 equal parts; 1 parts are shaded altogether.

Watch for: Treats the denominator as a count of selected pieces instead of the number of equal parts in one whole.

Try: Outline one whole first. Count all the equal pieces that fill it, label one piece 1/b, then repeat that piece until the whole is covered with no gaps.

s4: What fraction is shaded? Write its value.

Strip model: 1 same-sized whole, each divided into 4 equal parts; 2 parts are shaded altogether.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

h1: Design two exhibits for one half.

Watch for: Changes one part of a fraction without scaling numerator and denominator by the same factor.

Try: Shade 2/3 of a fixed strip and split each third into two equal parts. Count four shaded sixths out of six. Write ×2 on both arrows and check that the shaded endpoint did not move.

Look for in the response:

  • Create two different partitioned exhibits for one half.
  • Use equal-sized wholes and equal parts within each exhibit.
  • Show that both shaded amounts cover half, such as 1/2 and 2/4.

h2: Curate an exhibit labeled 2/3 on a strip with two of four parts shaded.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

Look for in the response:

  • Identify the mismatch between the 2/3 label and two of four shaded parts.
  • Repair the label to 2/4 (or 1/2), or redraw thirds with two shaded.
  • Explain why the repaired label now matches both total and shaded counts.

h3: Write a museum note about whole fractions such as 3/3.

Watch for: Does not recognize that b copies of 1/b make one whole.

Try: Fill one outlined whole with b equal pieces and label the completed whole b/b. Exchange the complete collection for a card labeled 1; do the exchange again with a different partition.

Look for in the response:

  • Explain that 3/3 includes all three thirds.
  • State that these equal parts fill one whole.
  • Extend the note to fractions such as b/b rather than suggesting all fractions equal one.

h4: Give feedback on uneven partitions without rejecting the artist.

Watch for: Counts pieces without checking equal area.

Try: Keep one rectangle fixed. Draw four unequal pieces beside four equal-area pieces. Ask which set lets every piece be called one fourth, then have the learner repair the unequal partition.

Look for in the response:

  • Identify uneven part areas as the mathematical issue.
  • Give a specific revision that equalizes the partition sizes.
  • Use feedback that addresses the model constructively and preserves an accurate fraction label.

e1: Compare 1/2 and 3/6. Choose <, =, or >. The wholes are the same size.

Watch for: Changes one part of a fraction without scaling numerator and denominator by the same factor.

Try: Shade 2/3 of a fixed strip and split each third into two equal parts. Count four shaded sixths out of six. Write ×2 on both arrows and check that the shaded endpoint did not move.

e2: Give one check you would use before displaying a model.

Watch for: Counts pieces without checking equal area.

Try: Keep one rectangle fixed. Draw four unequal pieces beside four equal-area pieces. Ask which set lets every piece be called one fourth, then have the learner repair the unequal partition.

Watch for: Reverses the shaded count and the total equal-part count.

Try: Use two labels: “equal pieces in one whole” under the bar and “pieces selected” above it. Point to every piece while naming the denominator, then only the selected pieces while naming the numerator.

Look for in the response:

  • Name a concrete pre-display check such as equal areas or label-to-count agreement.
  • State what feature of the model is inspected, such as the part areas or selected count.
  • Use a condition that establishes mathematical accuracy of the fraction exhibit.

Materials for your group

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Preview the complete lesson

Eight core questions and a two-question exit ticket. Print one set per student.

c1. What fraction is shaded? Write its value.

1 whole, each divided into 2 equal parts; 1 parts shaded in all.Each complete strip = 1 whole

c2. What fraction is shaded? Write its value.

1 whole, each divided into 4 equal parts; 2 parts shaded in all.Each complete strip = 1 whole

c3. What fraction is shaded? Write its value.

1 whole, each divided into 6 equal parts; 3 parts shaded in all.Each complete strip = 1 whole

c4. What fraction is shaded? Write its value.

1 whole, each divided into 8 equal parts; 4 parts shaded in all.Each complete strip = 1 whole

c5. Compare 1/2 and 2/4. Choose <, =, or >. The wholes are the same size.

c6. Compare 2/3 and 4/6. Choose <, =, or >. The wholes are the same size.

c7. Compare 3/4 and 6/8. Choose <, =, or >. The wholes are the same size.

c8. Compare 2/2 and 3/3. Choose <, =, or >. The wholes are the same size.

e1. Compare 1/2 and 3/6. Choose <, =, or >. The wholes are the same size.

e2. Give one check you would use before displaying a model.

Teaching notes & lesson sources

Designed for Grade 3. Create and critique exhibits showing equal fraction values.

3.NF.A.3b curriculum reference

Version 1.0.0. Original, AI-assisted lesson content. Free local classroom use; public reuse terms have not yet been assigned.

These lessons have not yet been field-tested in classrooms. Use the exit ticket and student explanations to decide what to revisit.