KS1 Problem Solving is a progressive series of books which help children to sharpen their mathematical skills by applying their knowledge to a range of 'real-life' situations such as shopping and telling the time. KS1 Problem Solving Book 3 includes: using a hundred square, odd and even numbers, addition and subtraction to 100, right angles and measuring with a ruler, counting money, calculating change, converting pence to pounds and reading a calendar.