Additive Pattern Focus

Overview

Today students will investigate additive patterns that grow or shrink by a constant amount. They will recognise the pattern rule, describe it clearly, create their own patterns using objects and shapes, and identify missing elements.

Learning intentions

Students will:

• recognise additive patterns that increase or decrease by a constant amount
• describe pattern rules using words and number sentences
• create additive patterns using numbers, shapes, or objects
• identify missing elements in an additive pattern and explain how they know

Success criteria

Students can:

• continue a pattern correctly for the next few terms
• state the constant change (how much is added or subtracted each time)
• describe what comes next using clear language (e.g. “add 3 each time”)
• find a missing number, shape, or object in the pattern and justify it

Curriculum links

• Algebra — VC2M2A01: recognise, describe and create additive patterns that increase or decrease by a constant amount; identify missing elements using numbers, shapes and objects
• VC2M2A01 achievement standard focus: apply understanding of patterns and sequences to interpret and generate terms
• Mathematical practices (implicit in VC2M2A01): reasoning, communication, and using representations to explain pattern rules

Lesson structure (60 minutes)

1. 0–7 min · Launch with a pattern. Teacher displays a growing pattern on the board (e.g. shapes or counters: ◆, ◆◆, ◆◆◆, …) and asks “What is changing each time?” Students do a quick think on their mini-whiteboards, then share with a partner.

2. 7–15 min · Whole-class direct teaching. Teacher explicitly models:

• finding the constant amount of change
• describing the rule (increase/decrease by the same amount each step)
• writing a simple number rule (e.g. “Start at 2, add 3 each time”) Students help label the constant change and use sentence starters: “Each step I ____ ____.”

3. 15–26 min · Guided practice: continue and describe. Teacher gives three short pattern strings (number and then shape/object). For each, students work in pairs to:

• circle the constant change
• write the next term(s)
• say a rule in one sentence Teacher circulates, prompting: “How do you know it’s the same each time?”

4. 26–40 min · Missing element challenge (VC2M2A01 focus). Students complete a worksheet or card set with patterns where one term is missing (including both numbers and pictures of objects/shapes). Teacher says: “Your job is to find the missing term and write the rule you used.” Students must show reasoning using either: a) counting on/off by the constant amount, or b) using repeated addition/subtraction from the starting term.

5. 40–53 min · Create your own pattern. In small groups of 3–4, students choose one of two tasks:

• Create a pattern using counters/connecting cubes and photograph or draw it: at least 5 terms.
• Create a shape pattern on provided grids (e.g. a repeating “add X” rule using square/circle tiles), then label the constant change. Each group writes: starting amount + constant change (increase or decrease). Teacher prompts groups to ensure the change is constant, not accidental.

6. 53–58 min · Share and check. Selected groups present one pattern. Classmates check using a “Rule–Test–Fix” routine:

• “What is the rule?”
• “Does the next term match?”
• If incorrect, students explain the correction.

7. 58–60 min · Exit ticket. Students complete one quick item: a partially shown additive pattern with a missing term (one number or one shape count). They write the rule in one sentence.

Resources

• Counters, connecting cubes or unifix blocks (plus spare for groups)
• Pattern cards showing additive patterns (growing and shrinking)
• Shape tiles/cut-outs (or printed shape arrays) for creating patterns
• Mini-whiteboards and markers
• Student worksheet or task cards with missing elements
• Sentence starter strips: “I add/subtract ___ each time.” “The pattern rule is…”
• Grid paper for shape patterns, plus colouring pencils
• Timer or visual countdown for transitions

Assessment

• Formative during guided practice: teacher listens for whether students identify the constant change and can describe the rule
• Worksheet check: accuracy of next terms and correct missing elements, with brief written explanations
• Exit ticket: students state the constant amount and give the missing term correctly

Differentiation

• Support:
• Provide sentence starters and a “Constant Change” checklist (add / subtract, and by how much)
• Use concrete-to-pictorial: first model with counters, then match the same pattern to a drawn version
• Offer a partially filled example where students only supply the missing term
• Extension:
• Ask students to create two different patterns that share the same constant change but different starting values
• Challenge students to predict the 10th term by continuing the pattern without drawing every term
• EAL/SEN considerations:
• Keep language consistent: “each time”, “add”, “subtract”, “same amount”
• Allow students to explain using drawings or acting out the pattern with counters before writing