L4 4-Digit Column Subtraction, with exchanges

This comprehensive Year 4 Autumn Term lesson plan focuses on teaching formal columnar subtraction of four-digit numbers with exchanges. Building on prior learning from Year 3 and the earlier subtraction lesson, the starter activity revisits place value and previously taught written subtraction methods to ensure pupils have a strong foundation before progressing. The introduction uses clear, step-by-step modelling to demonstrate how to subtract when an exchange is required. A place value chart supports conceptual understanding as pupils see why subtraction cannot be completed without regrouping, and how to exchange one ten for ten ones. Multiple worked examples—including paired whiteboard tasks—allow children to practise the method in guided stages, giving the teacher valuable opportunities to check understanding. During the independent activity, pupils select cut-up question cards and solve each subtraction in their maths books using the column method. Differentiation is built in through the optional use of place value counters or base-10 equipment for children who need concrete support when working with exchanges. The plenary reinforces key learning by asking pupils what to remember when making an exchange and analysing a sample calculation that contains a common error. This helps children identify misconceptions such as forgetting to exchange, subtracting in the wrong order, or failing to adjust the exchanged digit correctly. The resource outlines frequent errors, assessment opportunities, and key teaching points, making it fully aligned with the National Curriculum objective for pupils to add and subtract numbers with up to four digits using formal written methods. This lesson provides a structured, mastery-based approach to confidently teaching column subtraction with exchanges.