Fraction Classroom

Grade 4 / Comparing fractions

Benchmark Sort

Use one half as a benchmark to classify and compare fractions.

45 min · Grade 4 · Paper and pencils

Teaching companion · Version 2.0.0

Diagnose, reteach, and choose the next step

Use one half as a benchmark, and know when that benchmark cannot finish a comparison.

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. Without dividing, decide whether 3/7 is below or above one half.

    Answer and teaching response for d1

    Look for: Below one half: two copies give 6/7, still below one whole.

    If you observe: Rounds half of seven to three and calls 3/7 exactly one half.

    Respond: Pair two copies of the three selected sevenths; notice that six pieces still leave one seventh unfilled.

  2. Both 3/4 and 5/6 exceed one half. Does that fact tell which is larger?

    Answer and teaching response for d2

    Look for: No. More evidence is needed; 9/12 < 10/12 shows 3/4 < 5/6.

    If you observe: Orders them using only their shared “above half” category.

    Respond: Place both in the above-half region, then repartition into twelfths to locate their distinct endpoints.

Double the selected amount

  1. For 7/12, mark six twelfths as half and compare seven twelfths with it.
  2. For 3/7, compare two selected copies with all seven pieces instead of rounding half of seven.
  3. Sort examples below, at, and above half, then identify a pair needing more evidence to order.

Check independently: Where does 5/11 lie relative to one half? Explain with twice the numerator.

Answer to the reteaching check

Below half, because 2 × 5 = 10 is less than 11.

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

Read both exit responses

  • e1 gives > for 7/12 compared with 1/2.
  • e2 explains that comparing twice the numerator with the denominator compares two copies of the fraction with one whole.

Ready to continue

e1 meets its criterion: e1 gives > for 7/12 compared with 1/2. e2 also meets its criterion: e2 explains that comparing twice the numerator with the denominator compares two copies of the fraction with one whole.

Continue to the linked next lesson. Choose common units or another argument when fractions lie on the same side of one half.

Next lesson: Compare And Defend

Revisit the calculation or model

e1 does not yet meet this criterion: e1 gives > for 7/12 compared with 1/2.

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 explains that comparing twice the numerator with the denominator compares two copies of the fraction with one whole.

Use two seven-twelfth selections and ask the learner to connect 14 > 12 with the original one-half comparison, not just recite “double it.”

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: Compare 7/12 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c2: Compare 3/8 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c3: Compare 4/8 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c4: Compare 5/6 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c5: Compare 2/5 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c6: Compare 6/10 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c7: Compare 3/7 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

c8: Compare 5/10 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

s1: Compare 1/4 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

s2: Compare 2/4 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

s3: Compare 3/4 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

s4: Compare 1/3 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

h1: Explain where 7/12 belongs without dividing.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

Look for in the response:

  • Identify 6/12 as one half.
  • Compare seven twelfths with six twelfths without decimal division.
  • Place 7/12 above one half.

h2: Name two fractions below half with different denominators.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

Look for in the response:

  • Name two fractions with different denominators.
  • Make both fractions strictly below one half.
  • Verify each using a model or 2 × numerator < denominator.

h3: Can the benchmark alone compare 3/4 and 5/6?

Watch for: Compares unlike fractions using only the numerator, denominator, or an insufficient shared benchmark.

Try: Rename 2/3 and 3/4 as 8/12 and 9/12 on identical wholes. Compare the counts of twelfths. If both fractions lie above one half, ask for this additional evidence before ordering them.

Look for in the response:

  • State that being above one half does not by itself order 3/4 and 5/6.
  • Supply additional comparison evidence, such as 9/12 and 10/12.
  • Conclude 3/4 < 5/6.

h4: Invent a fraction between one half and one.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

Look for in the response:

  • Choose a fraction strictly greater than 1/2.
  • Verify that the same fraction is strictly less than 1.
  • Justify both bounds with equal parts, a line, or numerical inequalities.

e1: Compare 7/12 and 1/2. Choose <, =, or >. The wholes are the same size.

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

e2: How does twice the numerator help?

Watch for: Judges position relative to one half from numerator or denominator alone.

Try: For a/b, compare two copies of a selected parts with all b parts. If 2a is less than, equal to, or greater than b, the original fraction is below, at, or above one half. Test 3/7 by comparing 6 with 7.

Look for in the response:

  • Relate doubling the numerator to two copies of the fraction.
  • Compare that doubled count with the denominator representing one whole.
  • Explain the below/equal/above-half decisions, including 14 > 12 for 7/12.

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. Compare 7/12 and 1/2. Choose <, =, or >. The wholes are the same size.

c2. Compare 3/8 and 1/2. Choose <, =, or >. The wholes are the same size.

c3. Compare 4/8 and 1/2. Choose <, =, or >. The wholes are the same size.

c4. Compare 5/6 and 1/2. Choose <, =, or >. The wholes are the same size.

c5. Compare 2/5 and 1/2. Choose <, =, or >. The wholes are the same size.

c6. Compare 6/10 and 1/2. Choose <, =, or >. The wholes are the same size.

c7. Compare 3/7 and 1/2. Choose <, =, or >. The wholes are the same size.

c8. Compare 5/10 and 1/2. Choose <, =, or >. The wholes are the same size.

e1. Compare 7/12 and 1/2. Choose <, =, or >. The wholes are the same size.

e2. How does twice the numerator help?

Teaching notes & lesson sources

Designed for Grade 4. Use one half as a benchmark to classify and compare fractions.

4.NF.A.2 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.