Myths about teaching can hold you back
- Year 8
Checking understanding of perimeter
I can find the perimeter of many polygons or compound shapes.
- Year 8
Checking understanding of perimeter
I can find the perimeter of many polygons or compound shapes.
Lesson details
Key learning points
- The perimeter of any polygon can be found by summing the sides.
- The perimeter of shapes made from polygons can be found.
- Some methods for finding perimeters are more efficient than others.
- Missing lengths can be found when the perimeter is known.
Keywords
Perimeter - the distance around a 2D shape
Polygon - flat (2D), closed figure made up of straight line segments
Compound/composite shape - a shape created using two or more basic shapes
Common misconception
Summing all of the given lengths and only the given lengths to find the perimeter.
With each example discuss which lengths are part of the perimeter, which lengths are not and whether any lengths are equal to others.
To help you plan your year 8 maths lesson on: Checking understanding of perimeter, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 8 maths lesson on: Checking understanding of perimeter, download all teaching resources for free and adapt to suit your pupils' needs.
The starter quiz will activate and check your pupils' prior knowledge, with versions available both with and without answers in PDF format.
We use learning cycles to break down learning into key concepts or ideas linked to the learning outcome. Each learning cycle features explanations with checks for understanding and practice tasks with feedback. All of this is found in our slide decks, ready for you to download and edit. The practice tasks are also available as printable worksheets and some lessons have additional materials with extra material you might need for teaching the lesson.
The assessment exit quiz will test your pupils' understanding of the key learning points.
Our video is a tool for planning, showing how other teachers might teach the lesson, offering helpful tips, modelled explanations and inspiration for your own delivery in the classroom. Plus, you can set it as homework or revision for pupils and keep their learning on track by sharing an online pupil version of this lesson.
Explore more key stage 3 maths lessons from the Perimeter, area and volume unit, dive into the full secondary maths curriculum, or learn more about lesson planning.
Equipment
Licence
Prior knowledge starter quiz
6 Questions
Q1.Which of these units are a measure of length?
Q2.The image shows a wall whose length has been measured in four parts. The total length of the wall is m.

Q3.Which length is equal to $$a$$?

Q4.A shape is a shape created using two or more basic shapes.
Q5.Solve the equation: $$20 = 12 + a$$
Q6.Solve the equation: $$2a + 8 = 18$$
Assessment exit quiz
6 Questions
Q1.The is the distance around a 2D shape.
Q2.Which of the units could be used to measure perimeter?
Q3.What is the perimeter of the rectangle?

Q4.When $$a = 5$$ the perimeter of the octagon is mm.

Q5.The perimeter of the hexagon is 24 cm. Find the value of $$a$$.

Q6.The perimeter of the compound rectilinear shape is cm.
