Integers Start

Overview

Students will be introduced to integers as a number system that extends whole numbers using positive and negative values. The lesson focuses on interpreting signs, using a number line model, and applying simple addition rules using integers.

Learning intentions

• Students will understand that integers include positive and negative whole numbers, including zero.
• Students will locate and compare integers on a number line using the sign correctly.
• Students will model integer addition using real-world contexts and number-line moves.
• Students will explain why the sign changes when combining integers with opposite directions.

Success criteria

• I can identify a number as positive, negative, or zero and describe what the sign means.
• I can plot and order integers on a number line and justify my placement.
• I can solve simple addition of integers using a number-line strategy.
• I can check my answer by using the opposite move (inverse idea) or by re-reading the context.

Curriculum links

• Number — use the 4 operations with integers, choosing efficient strategies (including number lines and patterns).
• Number — recognise the effect of sign in multiplication of integers as a foundation concept (sign rules start with sign meaning).
• Algebra and Number connection — use properties and efficient strategies that support regrouping when operations involve negatives.

Lesson structure (30 minutes)

1. 0–5 min · Hook with context. Teacher shows four quick statements (e.g., “sea level drops by 3 m”, “temperature rises by 2°C”, “finish level is +5”), and asks what the + or − suggests. Students respond using mini whiteboards or verbal answers: “+ means up/increase, − means down/decrease; 0 means no change”.

2. 5–12 min · Direct teach: what integers are. Teacher models a vertical number-line style representation on the board and builds a number bank: −5, −2, 0, 3, 7, emphasising “integers” and the meaning of sign. Students copy the integer definition into their notes and complete a quick “classify the number” task: write each number under Positive / Negative / Zero.

3. 12–18 min · Guided practice: number line moves. Teacher demonstrates how to add integers using moves on a horizontal number line (start at one integer, move right for +, move left for −), including at least one case that crosses zero. Students complete four guided questions in pairs (or individually if only one student):

• −2 + 3
• 4 + (−6)
• −5 + (−2)
• 3 + (−3) Teacher checks placement and asks each student to describe the move: “Start at __, move __, land on __.”

4. 18–25 min · Efficient strategy check (pattern and reason). Teacher introduces a simple reasoning strategy using “opposites” and patterns:

• If two integers are the same distance from 0 but opposite signs (e.g., 5 and −5), their sum is 0.
• Adding a negative is the same as moving left. Students answer a short reasoning set (1 minute each, quick oral + written):
• What is −7 + 7? Explain using a number-line idea.
• Which is larger: −1 or −3? Explain without calculating far away.
• True/False: −4 + 2 is positive. (Choose and justify.)

5. 25–30 min · Exit ticket and consolidation. Teacher collects a 3-question exit ticket and records misconceptions for next lesson:

• Place −3, 0, +4 on a number line (label positions).
• Compute: 2 + (−5).
• Explain: Why does adding −2 move you left? (one sentence)

Resources

• Board/whiteboard or interactive display
• Printed integer cards or number strips (include negatives and zero)
• Number line template (−10 to +10) for student use
• Mini whiteboards or scrap paper for quick checks
• Exit ticket slips
• Marker pens, pencils, and erasers
• Optional: physical counters with two colours for positives/negatives

Assessment

• Formative: teacher circulates/observes during classification and number-line placement (focus on correct sign meaning).
• Formative: check student explanations of number-line moves (right = +, left = −, crossing zero).
• Summative-for-today: exit ticket scoring using a simple rubric: correct placement, correct sum, and an accurate explanation of sign/move.

Differentiation

• Support: provide a partially completed number line with arrow guidance (“right is +, left is −”); include sentence starters such as “I start at … then I move … because …”.
• Support for processing: reduce written workload by allowing answers to be recorded as number-line steps (e.g., “Start −5 → +3 steps right → −2”).
• Extension (for accuracy): ask “Find two different additions that give the same result as −1 (e.g., −3 + 2). Explain the pattern.”
• If EAL/SEN: emphasise consistent language frames: “positive means above zero/up, negative means below zero/down, zero means neither.”