1. Mathematical challenges for able pupils Year 4 D Calculating, measuring and understanding shape

2. You can put only one counter in each space.
Odds and evens
Copy this 5 by 5 grid.
Put 13 counters on it.
You can put only one counter in each space.
1. Place 13 counters. Get an odd number of them in each row and column and the two main diagonals.
Learning Objective:
Solve mathematical problems or puzzles.
Recognise odd and even numbers.
Explain methods and reasoning.

3. Odds and evens Copy this 5 by 5 grid. Put 10 counters on it.
You can put only one counter in each space.
2. Place 10 counters.
Get an even even number of them in each row and
column and the two main diagonals.
Learning Objective:
Solve mathematical problems or puzzles.
Recognise odd and even numbers.
Explain methods and reasoning.

4. Solution to Odds and evens
Several solutions are possible. For example:
Learning Objective:
Solve mathematical problems or puzzles.
Recognise odd and even numbers.
Explain methods and reasoning.

5. Joins can go up, down or sideways, but not diagonally.
Join any four numbers.
Find their total.
Joins can go up, down or sideways, but not diagonally.
The score shown is
= 47. 8 15 6 9 14 13 18 20 17 2 5 3 19
Find the highest possible score.
Find the lowest possible score.
Learning Objective:
Solve mathematical problems or puzzles.
Add and subtract two-digit numbers mentally.

6. Joins can go up, down or sideways, but not diagonally.
Try joining five numbers.
Find their total.
Joins can go up, down or sideways, but not diagonally. 8 15 6 9 14 13 18 20 17 2 5 3 19
Find the highest possible score.
Find the lowest possible score.
Learning Objective:
Solve mathematical problems or puzzles.
Add and subtract two-digit numbers mentally.

7. 8 15 6 9 14 13 18 20 17 2 5 3 19 Joins Try joining five numbers.
Now try joining five numbers using only diagonal joins. 8 15 6 9 14 13 18 20 17 2 5 3 19
Find the highest possible score.
Find the lowest possible score.
Learning Objective:
Solve mathematical problems or puzzles.
Add and subtract two-digit numbers mentally.

8. Solution to Joins Using four numbers:
the highest score is = 69,
the lowest score is = 30.
Using five numbers:
the highest is = 86,
the lowest is = 37.
Using five numbers and diagonal joins:
the highest is = 83,
the lowest is = 47.
Learning Objective:
Solve mathematical problems or puzzles.
Add and subtract two-digit numbers mentally.

9. The end,thank you!

10. References and additional resources.
The questions from this PowerPoint came from:
Mathematical challenges for able pupils in Key Stages 1 and 2
Corporate writer was Department for Education and Employment and it is produced under a © Crown copyright 2000
Thank You
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These Mental Maths challenges can be found as a PDF file at :
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All images used in this PowerPoint was found at the free Public Domain Clip Art site. (
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