3rd grade irregular plural nouns worksheets
Irregular plurals change form (mice, feet, children) or refuse to change at all (sheep, deer, fish). Third graders solidify the core set and pick the correct form over tempting inventions like childs, sheeps, and mices.
Free printable PDF worksheet, aligned to Common Core L.3.1.b.
A new sheet every click.
The kind of sentences you'll get
Circle the letter of the correct plural.
-
In science class, we counted the model skull’s thirty-two .
teeths · teeth · tooths
Answer: teeth
- Two lost wandered down the mountain path. sheeps · sheep
- From the porch, we watched five cross the yard. deer · deers
Every print pulls a fresh set of sentences at this level, so a make-up test or a second sibling never gets the same sheet.
What's on each sheet
- Choose the word. Circle the letter of the correct plural. 10 questions per page.
Every version prints on US Letter or A4, with its answer key on the last page.
How to teach this
Split the set in two: words that change (mice, geese, men) and words that stay put (sheep, deer, fish). The stay-put group surprises kids most, so give it explicit attention: "five sheep" feels wrong to a child who has internalized add-s. Keep the number cue front and center in every practice sentence.
Watch for: Some plurals don't change at all: one sheep, five sheep; one deer, three deer. The number word does all the work. Double-marked forms like mices or feets are never right; the changed word is already plural.
Common questions about irregular plural nouns
- Why don't sheep and deer change in the plural?
- They're ancient herd-animal words that never took a plural ending, and English kept the habit. The sentence carries the number instead: five sheep, both deer. Kids handle it best as a short memorized list (sheep, deer, fish, moose) rather than as a rule.
- Is "fishes" ever correct?
- In everyday writing, no; the plural of fish is fish. Scientists do say fishes when they mean several different species, and one of our 4th grade items nods to that. For 3rd grade purposes, fish is the safe and expected answer.
Related worksheets
- 2nd grade irregular plural nouns A step easier, same skill
- 4th grade irregular plural nouns A step harder, same skill
- 3rd grade adverbs of how, when, and where Same grade, nearby skill
- 3rd grade articles (a, an, the) Same grade, nearby skill
- 3rd grade collective nouns Same grade, nearby skill
- Irregular plural nouns, all grades The full progression
- All 3rd grade English worksheets Every skill at this level
- All 3rd grade worksheets Everything at this level
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Aligned to Common Core L.3.1.b. Reviewed by the One more sheet team. Content version 137, updated August 2026.
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