Grade 4 · Mathematics · 25 minutes

Factors and multiples

Build rectangles with 24 counters. Factor pairs multiply to a given whole number.

Mr. S Teaches · Starter mini-lesson · elem-4-factors-and-multiples

Learning objective

Explain and practice factors and multiples using the activity and evidence, then show the reasoning behind an answer.

Gather your materials

Paper and pencil
Counters, blocks or paper pieces
A ruler, clock model or grid when named in the steps

Use the items named in the teaching steps; paper models or adult-prepared photographs can replace physical equipment.

Common Core skill focus

4.OA.B.4

Find factors and identify multiples, prime numbers, and composite numbers within one hundred.

Read the official standard ↗

Code and grade verified 2026-11-03. This mini-lesson addresses a selected skill, not the entire standard.

Teach it step by step

Build rectangles with 24 counters.
Record side lengths as factor pairs.
Check pairs in order until the pairs begin repeating.
Use the list to decide whether 24 is prime or composite.

Watch, notice, discuss

Video choices for this lesson

2 choices

Preview a video, then choose what fits your learners. “Show to class” opens a larger view; use the player’s play and full-screen controls when you’re ready.

Teacher preview needed. Check the language, level and length before showing. YouTube may show ads or related videos.

OPTION 1 · YOUTUBE

Factors and multiples | MightyOwl Math | 4th Grade

By MightyOwl

Connect this video to the lesson on factors and multiples. Pause to try an example together.

Open on YouTube: Factors and multiples | MightyOwl Math | 4th Grade (opens a new tab) ↗

OPTION 2 · YOUTUBE

Factors, Multiples, Prime & Composite - 4th Grade Math [For TEACHERS & PARENTS]

By McCarthy Math Academy

Teacher/parent refresher: select a short explanation to adapt for the class.

Open on YouTube: Factors, Multiples, Prime & Composite - 4th Grade Math [For TEACHERS & PARENTS] (opens a new tab) ↗

After watching

Find factor pairs and some multiples of a number. Explain the difference.

An external player loads only after you choose Preview or Show to class. Playback connects to YouTube. Videos belong to their creators; availability and embedding can change.

Make the thinking visible

Example to work through together

The factor pairs are 1×24, 2×12, 3×8 and 4×6. More than one pair makes 24 composite.

Try the starter activity

List every pair that multiplies to 24.

Student practice

List the factor pairs of 18 and decide whether it is prime or composite.

Quick check for understanding

Is 24 prime or composite?

Sample answer and teacher guidance

Sample answer: Composite: pairs include 1×24, 2×12, 3×8, 4×6.

Listen or look for: 1×18, 2×9 and 3×6; composite.

Invite the learner to explain, demonstrate, draw or dictate their reasoning. Revisit a teaching step when the explanation is unclear.