Reasoning and Convincing is part of our Developing Mathematical Thinking collection.
John Mason talks about convincing yourself, convincing a friend and convincing a sceptic. If your pupils don't know what a sceptic is, now's a good time to help them to understand!!
problem
Beads and bags
Age
5 to 11
Challenge level
How could you put these three beads into bags? How many different ways can you do it? How could you record what you've done?
problem
If the world were a village
Age
5 to 11
Challenge level
This activity is based on data in the book 'If the World Were a Village'. How will you represent your chosen data for maximum effect?
problem
The puzzling sweet shop
Age
5 to 11
Challenge level
There were cola bottles for 2p, mini eggs for 3p, marshmallow twists for 5p and lollipops for 7p in the sweet shop. What could each of the children buy with their money?
problem
Money bags
Age
5 to 11
Challenge level
Ram divided 15 pennies among four small bags. He could then pay any sum of money from 1p to 15p without opening any bag. How many pennies did Ram put in each bag?
problem
Mathdoku
Age
7 to 11
Challenge level
Complete the Mathdoku grid using the clues. Can you convince us that the number you have chosen for each square has to be correct?
problem
Magic Vs
Age
7 to 11
Challenge level
Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?
problem
Guess the dominoes
Age
7 to 11
Challenge level
This task depends on learners sharing reasoning, listening to opinions, reflecting and pulling ideas together.
problem
Fifteen cards
Age
7 to 11
Challenge level
Can you use the information to find out which cards I have used?
problem
Less is more
Age
7 to 11
Challenge level
Use your knowledge of place value to try to win this game. How will you maximise your score?
problem
Sealed solution
Age
7 to 11
Challenge level
Ten cards are put into five envelopes so that there are two cards in each envelope. The sum of the numbers inside it is written on each envelope. What numbers could be inside the envelopes?
problem
Six ten total
Age
7 to 11
Challenge level
This challenge combines addition, multiplication, perseverance and even proof.
problem
What's it worth?
Age
11 to 16
Challenge level
There are lots of different methods to find out what the shapes are worth - how many can you find?