Year 4 · Angles, shapes and position
Sorting triangles and quadrilaterals
Compare and classify geometric shapes, including quadrilaterals and triangles, based on their properties and sizes
Lesson overview
What you'll learn in this lesson
Compare and classify geometric shapes, including quadrilaterals and triangles, based on their properties and sizes
Key learning points
- • Three kinds of triangle
- • Shapes do not change when you turn them
- • The quadrilateral family
- • Sorting with a table
This lesson at a glance
- 20 minutes
- 19 parts to scroll through
- 4 quick checks
- No marked quiz yet
- Gentle pace: short sittings with pauses
Words to know
Scroll down — the lesson carries on below
Watch & discover
Part 1 of 19
Watch first
Sorting triangles and quadrilaterals
Learn to spot acute, right, obtuse and reflex angles anywhere.
Do it for real
The practicals below use what the film shows, with a full method you can follow at home.
In a nutshell
Compare and classify geometric shapes, including quadrilaterals and triangles, based on their properties and sizes
What you already know
Part 2 of 19
Before we start
What you already know
You can name common 2-D shapes and identify lines of symmetry.
Key words
Part 3 of 19
Key words
Words you'll need today
- quadrilateral
- Any shape with four straight sides.
- isosceles
- A triangle with two equal sides.
- parallel
- Lines that stay the same distance apart forever.
Learning cycle
Part 4 of 19
Learning cycle 1 of 2
Part 1 — Triangles
A short piece of teaching, then a check to make sure it has landed.
Explore the idea
Part 5 of 19
Learn
Three kinds of triangle
Equilateral: three equal sides and three equal angles. Isosceles: two equal sides and two equal angles. Scalene: all sides different. A right-angled triangle has one square corner and can be isosceles or scalene.
Explore the idea
Part 6 of 19
Learn
Shapes do not change when you turn them
A triangle balanced on a point is still the same triangle. Test the properties, not the position — that is what 'in different orientations' means in the tests.
Quick check
Part 7 of 19
Quick check
A triangle with two equal sides is
Quick check
Part 8 of 19
Quick check
How many right angles does a rectangle have?
Reset break
Part 9 of 19
Pause
That's sitting 1 of 2 done
Stretch, get a drink, look out of the window. There is no timer and nothing is counting down — your place is saved, so you can come back in five minutes or tomorrow.
Learning cycle
Part 10 of 19
Learning cycle 2 of 2
Part 2 — Quadrilaterals
A short piece of teaching, then a check to make sure it has landed.
Explore the idea
Part 11 of 19
Learn
The quadrilateral family
Square: four equal sides, four right angles. Rectangle: opposite sides equal, four right angles. Rhombus: four equal sides, no right angles needed. Parallelogram: opposite sides parallel and equal. Trapezium: exactly one pair of parallel sides.
Explore the idea
Part 12 of 19
Learn
Sorting with a table
Draw two columns — has right angles, no right angles — and put each shape in one. Then try a different rule, like 'all sides equal'. Sorting the same shapes twice shows a square is also a rectangle and also a rhombus.
Quick check
Part 13 of 19
Quick check
A shape with exactly one pair of parallel sides is a
Quick check
Part 14 of 19
Quick check
A square turned 45° is
Common mix-ups
Part 15 of 19
Common mix-ups
Things people often get wrong
- Saying a rotated square is a diamond and so not a square.
- Thinking a rectangle must be long and thin.
- Believing a rhombus needs right angles.
Challenge round
Part 16 of 19
Game · Sort it
Which of these are true?
Drag each card into the right column. Tap a card first if dragging is fiddly.
True
Not true
Challenge round
Part 17 of 19
Game · Fill the gaps
Finish the sentences
Choose the word that belongs in each gap.
Sorting the same ____ twice shows a square is also a rectangle and also a rhombus.
Mastery quiz
Part 18 of 19
No quiz for this one
This lesson has no marked quiz attached yet.
Lesson round-up
Part 19 of 19
Lesson round-up
Ready when you are
Quiz score
Not sat
Games
Not played
Points this lesson
0
Best run
0 in a row
Luna: 0 out of 4 on the practice checks. Only if you feel up to it — one more?
Ask LunaDo the work
Your written work for this lesson
This is the part you'd do in your book at school. Pick the pieces below, write here or on paper, and photograph anything you draw or work out.
The cost of a school trip
A school is planning a trip to a wildlife park. The coach costs £480 however many people go. Entry costs £9.50 for each pupil and each adult goes free. The school says every pupil must pay the same amount, and the trip must not lose money.
If 60 pupils go, the coach works out at £8 each, so the total for each pupil is £17.50. If only 40 pupils go, the coach works out at £12 each, so the price rises to £21.50. The teacher explains that the coach is a fixed cost and the entry is a cost per person — which is why the price per pupil changes when the number changes.
The school decides to charge £20 and to use anything left over for a second trip later in the year.
Written for Good Learning Co.
Reading questions
- Work out the total cost of the trip if 50 pupils go.
- Show why the price per pupil falls when more pupils go, using numbers.
- At £20 each, how many pupils must go before the trip makes money? Show your working.
Working out
Working outDo the practice questions on paper, showing every step — not just the answer. Mark them yourself and circle anything you got wrong.
10–15 questions
Worked example, explained
WritingCopy one question out and write underneath, in words, why each step works.
1 question, 4–5 sentences
Problem in words
Working outWrite your own real-life problem that uses today's method, then solve it.
1 problem + solution
Saved as you type.
Part 1 of 19 · Watch & discover