This collection of tasks is part of the activities for 11-14 year olds section of the Maths At Home feature. The activities below are worth exploring over a few days, or even a few weeks! The stars represent the challenge level, with three stars indicating the most challenging activities.
You may also wish to explore Maths to Take Your Time Over for 7-11 year olds, and Maths to Take Your Time Over for 14-16 year olds.
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problem
Summing consecutive numbers
15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?
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problem
Reaction timer
This problem offers you two ways to test reactions - use them to investigate your ideas about speeds of reaction.
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problem
Fibonacci surprises
Play around with the Fibonacci sequence and discover some surprising results!
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problem
Squares in rectangles
A 2 by 3 rectangle contains 8 squares and a 3 by 4 rectangle
contains 20 squares. What size rectangle(s) contain(s) exactly 100
squares? Can you find them all?