Place this row where students can see it: RED BLUE | RED BLUE | RED BLUE. Ask, “What comes next?” A student may answer “red”. Then ask a different question: “What is the smallest part that keeps repeating?”
The answer to the second question is RED BLUE. It names the rule rather than only predicting one item. Three copies of this two-item core produce the six-item row. A correct prediction does not, by itself, explain what repeats.
The questions above separate two related tasks: continuing a pattern and identifying its repeating unit. The teaching sequence below focuses on finding and explaining that unit.
Start with the smallest complete core
The repeating unit is the smallest complete part that repeats. The NCETM pattern guidance distinguishes this unit from the longer displayed sequence, which may contain several copies.
Return to RED BLUE | RED BLUE | RED BLUE. A student might name RED BLUE RED BLUE as the part that repeats. It can repeat, but it is not the smallest choice. Cover the final pair and compare:
- RED BLUE repeats immediately.
- RED BLUE RED BLUE contains two copies of that smaller unit.
Say, “Both chunks can help us describe the row, but which is the smallest complete chunk that makes the whole pattern?” Introduce the word core after students have identified the chunk: “RED BLUE is the pattern core.”
Build and bracket an AB pattern
Give the student loose counters, blocks or paper shapes in two colours. Ask them to build RED BLUE and then repeat that exact arrangement. Keep the pieces movable so they can test a proposed core rather than relying only on the printed row.
- Build three complete copies of RED BLUE.
- Slide a finger under each pair while saying, “red, blue”.
- Separate the copies with small gaps or draw a bracket beneath each pair.
- Ask, “Where does one copy finish? Where does the next copy begin?”
- Close the gaps and ask the student to point out the core again.
If the student points to one red counter, ask, “Can red by itself make the next item blue?” If they select the whole row, ask, “Is there a smaller complete part inside your choice that repeats straight away?”
Challenge the alternating-only idea with ABB
Now present RED BLUE BLUE | RED BLUE BLUE | RED BLUE BLUE. Ask the same questions in the same order: “What comes next?” and “What is the smallest part that repeats?”
The core is RED BLUE BLUE. The adjacent blue items do not break the pattern; they belong to each complete copy. Invite the student to bracket the row, then say each core without pausing inside it: “red-blue-blue, red-blue-blue, red-blue-blue”.
Contrast the two examples directly:
| Displayed pattern | Smallest core |
|---|---|
| RED BLUE | RED BLUE | RED BLUE | RED BLUE |
| RED BLUE BLUE | RED BLUE BLUE | RED BLUE BLUE | RED BLUE BLUE |
Ask, “What stayed the same about our method?” A useful explanation is that the student looked for the smallest complete chunk that could be copied again and again.
Rebuild the rule with actions or new objects
Movable objects, varied pattern structures and representing a rule in another medium are suggested ways to explore repeating patterns in the NCETM guidance. Try changing the elements while keeping the structure.
Show RED BLUE | RED BLUE | RED BLUE, then perform CLAP TAP | CLAP TAP | CLAP TAP. Ask, “Which action matches red? Which action matches blue? Where is the action core?”
Next, offer two different objects, such as a circle and a triangle. Ask the student to make the same AB rule without copying the colours. A suitable response could be CIRCLE TRIANGLE | CIRCLE TRIANGLE | CIRCLE TRIANGLE. The objects have changed, but the order within the core has not.
Repair one substitution error
Display RED BLUE | RED RED | RED BLUE. Explain that one item has been replaced. Ask the student to find it without first naming the correct answer.
Compare complete pairs from the start:
- The first pair is RED BLUE.
- The second pair is RED RED.
- The third pair is RED BLUE.
Ask, “If RED BLUE is the core, what must the second pair look like?” Replace the red item in position four with blue. Then read the repaired row by complete cores: RED BLUE | RED BLUE | RED BLUE.
Follow with, “How did comparing whole cores help you find the change?” This keeps attention on the repeating rule instead of treating the task as a visual odd-one-out puzzle.
Use a fresh AAB exit check
Present a new row without gaps or separators: CIRCLE CIRCLE TRIANGLE CIRCLE CIRCLE TRIANGLE CIRCLE CIRCLE TRIANGLE. Do not label its structure first. Ask the student to mark the core boundaries themselves.
Ask three questions:
- “What is the smallest core?”
- “What comes next, and how does the core tell you?”
- “Can you show the same rule with actions or different objects?”
Teacher answer: CIRCLE CIRCLE TRIANGLE | CIRCLE CIRCLE TRIANGLE | CIRCLE CIRCLE TRIANGLE. A student might name CIRCLE CIRCLE TRIANGLE, explain that the next item is a circle because a new copy begins, and represent the rule as CLAP CLAP TAP.
Use the explanation to choose a follow-up. If the student predicts correctly but cannot isolate the core, return to movable pieces and brackets. If they choose a larger chunk containing several copies, ask them to search inside it for a smaller repeating part. If they identify the core confidently, offer ABB or AABB and ask for a new representation. One response should guide the next prompt, not serve as a claim of mastery.
Optional prepared resource
The Year 1 Repeating Patterns Unit from Sukindi Learning lists a “20-page unit plan PDF with all printable resources” and “Five low-ink worksheets with matching answer pages”. It is an optional prepared resource; the teaching sequence above can be used independently.
You can also browse the Year 1 teaching resources collection for related classroom materials.