Understanding Subtraction

Overview

This 30-minute active learning session introduces Foundation Stage students to the concept of subtraction. The class of 15 students will be divided into three ability groups, with differentiated activities tailored to each group's readiness, especially supporting lower-ability learners focusing on numbers below 10. The lesson aligns closely with the Northern Ireland Curriculum, specifically the Foundation Stage in Mathematics under the "Number Processes and Skills" area.

Curriculum Links (Northern Ireland Curriculum)

Mathematics and Numeracy
- Strand: Number Processes and Skills (Main focus)
- Learning Outcome FS_MN 1-3 (Number Processes and Skills):
  - Children use number words, number symbols and counting skills during practical play and everyday situations.
- Learning Outcome FS_MN 2-3:
  - Children understand concepts of addition and subtraction through everyday language and practical activities.
- Levels of Progression (Foundation Stage):
  - Beginning to use subtraction within 10, moving towards working with numbers beyond 10.
Thinking Skills and Personal Capabilities
- Using Thinking Skills: Applying and Reasoning
- Self-Management: Staying on task during collaborative activities

Learning Objectives

By the end of the lesson, learners will be able to:

Recognise subtraction as "taking away" objects from a group within 10 (lower ability).
Use practical materials to model subtraction problems (all groups).
Understand and use subtraction vocabulary: take away, subtract, less, difference (all groups).
Solve simple subtraction problems appropriate to their ability (numbers below 10 for lower ability, up to 20 for higher ability).

Resources

Counting objects (counters, cubes, or small toys)
Number cards (0-20)
Whiteboards and dry wipe markers
Subtraction story picture cards (scenarios like “Tom had 5 apples, he gave 2 away”)
Large visual number line (0–20) on the floor or wall
Small baskets or containers for grouping
Sand timers or visual timers for activity transitions

Lesson Structure

1. Introduction & Engagement (5 minutes)

Teacher Action:
Gather children in a circle, using real objects (e.g., 7 counters).
Introduce subtraction with a simple story: “I have 7 counters, I take away 2, how many are left?”
Use clear, age-appropriate vocabulary: "take away," "less," "how many left?"
Active Learning:
Invite 2-3 children to physically remove counters to demonstrate subtraction.
Assessment:
Ask open questions to check understanding: “What do we do in subtraction?” “How many counters are left?”

2. Group Activities by Ability (20 minutes)

Divide the children into three groups:

Group 1: Lower Ability (Numbers below 10)

Focus: Concrete subtraction with numbers up to 10.
Activity: "Take Away Basket"
Each child receives a basket with up to 10 counters. The teacher calls out subtraction sentences (e.g. "You have 5 counters, take away 2"). Children physically remove counters.
Support: Use number lines and fingers for counting back.
Extension: Use pictorial story cards showing subtraction scenarios. Children recount what has been 'taken away.'
Assessment: Teacher observes and questions to verify understanding of subtracting objects physically.

Group 2: Middle Ability (Numbers up to 15)

Focus: Concrete to pictorial subtraction and beginning use of symbols.
Activity: Subtraction Story Problems
Children use counters and number cards to model simple subtraction problems provided by the teacher (e.g., 12 – 5). Children draw or arrange counters accordingly, then write the matching subtraction sentence on their mini whiteboards (e.g., 12 – 5 = ?).
Extension: Discussion of words and symbols, using key vocabulary.
Assessment: Peer explanation of how they solved the problem.

Group 3: Higher Ability (Numbers up to 20)

Focus: Abstract subtraction with beginning mental subtraction.
Activity: Number Line Subtraction Race
Children work in pairs with a number line. Teacher calls out subtraction problems (e.g., 18 – 7). Children jump back on the floor number line to model the subtraction, then write the answer on whiteboards.
Extension: Children create their own subtraction word problems.
Assessment: Teacher asks reasoning questions – “If we take away 7 from 18, how do we find the answer on the number line?”

3. Plenary and Reflection (5 minutes)

Regroup and invite children to share their favourite subtraction activity or one new thing they learned.
Use a “Subtraction Song” or chant together to consolidate vocabulary and concept (e.g., “Take away, take away, what’s left today?”).
Quick flashcard questions: Show number cards 1-10, ask students to call out “Take away 2” and state how many remain.
Reinforce that subtraction means “taking away” and that objects or numbers get less.

Assessment and Feedback

Formative Assessment during activities: Continuous observation, questioning, and checking for correct use of vocabulary and understanding.
End of Lesson: Children show answers on mini whiteboards or with counters for one subtraction problem of their choice.
Teacher Notes: Note which children demonstrate confidence and which may need continued support in subsequent lessons.

Differentiation and Inclusion

Clear visual aids to support understanding.
Use of concrete objects for kinaesthetic learners.
Repetition of vocabulary with gestures for EAL or speech and language needs.
Extra adult or peer support for lower ability group.
Challenge the higher group with creating subtraction problems and explaining their reasoning aloud.

Reflection for Future Planning

Did the differentiation effectively meet learner needs?
Were the children engaged in physical, visual, and verbal learning?
How did the use of real objects and number lines support conceptual understanding?
Plan for next lesson: Progress towards simple subtraction within 20 using pictorial representations and number sentences.

This lesson plan harnesses active learning through concrete materials, movement, and storytelling, all rooted in the Northern Ireland curriculum standards, ensuring every child’s progression in understanding subtraction is nurtured from the Foundation Stage.