Crownfield Junior School Children HomeIntroduction Video

Year 6 Maths Facts | Year 5 Maths facts |
Year 4 maths facts | Year 3 maths facts | 

Mental Mathemagicians


Year 5 Maths facts


Number facts


1. Know fraction and decimal equivalents: 1/2 = 0.5, ¼ = 0.25, ¾ = 0.75, 0.2 = 1/5, tenths and hundredths.

2. Know that ‘per cent’ means ‘per hundred’ and a percentage is a number out of a hundred

3. Know that 100/100 = 100 %, 1/10 = 10%, 1/100 = 1%, ½ = 50% and ¼ = 25%.

4. Know the definitions for numerator and denominator:

Denominator: The bottom number when a fraction is written down which tells us how many parts the whole is split into.

2   2 is the denominator.

Numerator: The top number when a fraction is written down showing the number of parts of the whole.

4   3 is the numerator.

5. Know that a proper fraction has a larger denominator than numerator (e.g. 1/6 2/7 7/12)

6. Know that an improper fraction has a larger numerator than denominator (e.g. 7/4 5/3 3/2)

7. Know that a mixed fraction has a whole number and a fraction (e.g. 2 ½, 7 ¾)

Understanding shape

8. Know the name and properties of an octahedron: a regular polyhedron with a faces which are equilateral triangles

9. Know that a scalene triangle has no equal sides or angles

10. Know that a parallel line is of an equal distance to another line

11. Know that a perpendicular line is at right angles to another line

12. Know that acute angles are less than 90 degrees and obtuse angles are greater than 90 degrees but less than 180 degrees.

13. Know that the angles in a straight line add up to 180 degrees.

14. Know that the ‘x’ axis is horizontal and the ‘y’ axis is vertical.



15. Know that to calculate the area of a rectangle you must multiply the length by the width/breadth

16. Know that area is measured in cm squared

17. Know 12 hour and 24 hour time equivalents:

(1 pm = 13:00, 7pm = 19:00)

18. Know that to convert kilograms-grams, litres-millilitres, kilometres-metres, metres-millimetres you x 1000 (e.g. 4 km = 4000m, 4 L = 4000ml)

19. Know that to convert metres-centimetres you x 100 (e.g. 8m = 800cm)

20. Know that to convert centimetres-millimetres you x 10 (7cm = 70 mm)


Data Handling

21. Know that to find the mean of a set of numbers you add the numbers together and divide by the number of numbers



22. Know this scale for probability:

0 ¼ ,0.25 ½ 0.5 ¾ 0.75 1

No chance

unlikely even chance  likely




Memory trick - numerator and Downominator (the denominator is the bottom number in a fraction).



Memory tricks-

Look at the two l’s in Parallel: they are parallel lines!

Acute – less than 90 degrees; a ‘cute’ and small angle. Get children to show you acute, obtuse, right and straight angles with their arms.


The ‘X’ axis goes across the page.

12 and 24 hour equivalents

Use clocks around the house and ask the children the time on both the 12 and the 24 hour clock. Play around the clock: write the numbers 1-12 in random order around a circle. Point to each number as the child gives you the 24 hour equivalent. Try timing them – can they beat their time for getting the whole way around the circle?


Please note the facts for previous years. It is particularly important that tables facts are learnt by heart by year 5.

Crownfield School LogosCrownfield Junior School, White Hart Lane
Collier Row Essex RM7 8JB
01708 747070
Southend Web Design Studio | © 2014 Promote Local