Perimeter – Grade 3 math lesson

For parents: how to use this lesson

You don't need to know this topic yourself. The lesson explains each step on screen, the way Mr Euclid, our Head of Math, likes it: one tidy step at a time. Every answer is graded straight away with a worked explanation, so you never have to grade anything.

1. Read what your child will learn together.
2. Press Start the lesson below and sit with your child for the teaching and the worked examples (about 19 minutes).
3. Let them do the practice on their own. They choose Getting started, On track or Challenge – start on On track and move up after a few right in a row.
4. Finish with the exit ticket and the talk question: “What is the difference between perimeter and area?”
5. Later that day or the next day: the homework (15 minutes), then a practice test.

Watch out for

• Adding only the two sides that are labeled. Trace round the shape with a finger, saying each side.
• Multiplying the sides (finding the area). Perimeter is a length, so the answer is in cm or m, not cm².

Miss Hypatia's tip for home: Measure round a room, the garden or a photo frame.