Free printable practice
Prime Factors Practice Activities
Class 4 prime factors worksheets that help children break composite numbers into prime numbers using factor pairs, factor trees, and repeated division.
Practice that builds confidence
What children learn
These Class 4 maths worksheets help children understand that every composite number can be made by multiplying prime numbers. Learners practise identifying prime and composite numbers, finding factor pairs, and breaking numbers into prime factors step by step.
The printable activities include clear exercises with factor trees, repeated division, missing-factor questions, and short reasoning tasks. They are useful for strengthening factoring skills before children move on to multiples, common factors, and more advanced number work.
Prime factors are the prime numbers that multiply together to make a larger number. In these worksheets, children move from recognising small primes such as 2, 3, 5, 7, 11 and 13 to decomposing composite numbers like 12, 18, 24, 36 or 48. They learn that 12 can be written as 2 × 2 × 3, and that the order of the factors may change, but the prime factors remain the same.
Progression through the worksheets
Practice begins with sorting numbers as prime or composite and listing simple factor pairs. It then builds towards factor trees, where each branch is split until only prime numbers remain. Repeated division activities give another representation: divide by a prime number, continue with the quotient, and stop when the final number is prime. This variety helps children see prime factorisation as a process, not a trick.
A simple parent routine
At home, choose one number from the worksheet and ask, “Can we split this into two factors?” Write the pair, then check whether each factor is prime or can be split again. Encourage your child to circle the primes at the end and read the final multiplication sentence aloud. For example, 30 becomes 3 × 10, then 3 × 2 × 5. A quick check is to multiply the prime factors back to the original number.
Classroom use for teachers
Teachers can use these sheets during maths centres, small-group support, or independent factoring practice. One group can build factor trees, another can use repeated division, and a third can compare answers to see why different trees can still end with the same prime factors. The worksheets also work well for quick revision before lessons on common factors or divisibility.
Common errors to watch for
Children may stop too early, leaving a composite number such as 4, 6, 8 or 9 in the final answer. Some may confuse factors with multiples, or write all factors instead of only prime factors. Another common mistake is forgetting repeated factors, such as writing 36 as 2 × 3 instead of 2 × 2 × 3 × 3.
Free printable PDF download
Use this Class 4 prime factors worksheet page to preview the activity, print it, or download it as a PDF for quick practice. It works well for homework, homeschool lessons, tutoring, morning work, revision, and classroom centers.
Answers and answer key support
After the child completes the worksheet independently, parents and teachers can use the answer support or answer key information to check the work, review mistakes, and choose the next practice step.
Why iBloom worksheets help
The pages use structured layouts, clear number spaces, and mixed representations so children can connect factor pairs, factor trees, and division steps. A child-friendly strategy is: “Split, check, circle primes, multiply back.” This keeps the work organised and helps learners explain their reasoning with confidence.
Helpful answers
Frequently asked questions
What are prime factors in Class 4 maths?
Prime factors are prime numbers that multiply together to make a composite number. For example, the prime factors of 18 are 2, 3 and 3 because 2 × 3 × 3 = 18.
How do these worksheets teach prime factorisation?
They use factor pairs, factor trees, and repeated division so children can break a number down step by step until every remaining factor is prime.
What should my child know before starting these worksheets?
It helps if your child can multiply and divide small numbers, recognise basic factor pairs, and understand the difference between prime and composite numbers.
Why are different factor trees sometimes both correct?
A number can be split in different ways at first. For example, 24 can start as 3 × 8 or 4 × 6, but both trees should end with the same prime factors: 2 × 2 × 2 × 3.
How can I check my child’s prime factor answer?
Ask your child to multiply all the prime factors back together. If the product matches the original number and every factor is prime, the answer is correct.
Is this Class 4 prime factors worksheet free?
Yes. You can preview it for free and use the printable worksheet for home or classroom practice.
Can I download this Class 4 prime factors worksheet as a PDF?
Yes. Use the worksheet download option to save a printable PDF, or print the worksheet directly from the page.
Does this Class 4 prime factors worksheet include answers or an answer key?
When the activity has fixed answers, iBloom includes answer support so parents and teachers can check the completed worksheet.