Tricky Totals: Problem Solving 'Start the Day'

Do your children need practice solving problems and puzzles? Do you need activities that specifically practise reasoning with addition and subtraction? Then look no further than this ‘Start the Day’ activity pack.

This is the full pack which has 5 similar activities (each with teacher answers) in PDF form for easy printing and sharing with your children on an interactive whiteboard.

The activity is designed to encourage children to work systematically to find the correct totals. The 3 x 3 grid uses the digits 1-9 only once. Three different sections are colour-coded to represent a sum total of that colour, and the smaller sum totals represent the 4 touching squares around it. Children are forced to reason throughout, for example that if two blue squares total 8, the paired numbers must be either 1 + 7, 2 + 6, 3 + 5 but not 4 + 4 because the digit 4 cannot be used twice.

Tips on how to deliver these activities:

• On the first occasion you use these activities, allow children a free run at solving the puzzle, perhaps with some very minor discussion around the sum totals and how they might help;
• Allow children to use the digit cards 1-9 to physically manipulate their puzzle;
• Allow children to talk through their strategies for finding solutions, encouraging pupil voice in both paired and whole-class discussions;
• If necessary (some children won’t find a way to solve the problem without a system), share a way to work backwards. For example, what piece of information helps us the most. Can we start from there? Why can’t a 5 go here? Etc;
• Encourage children to think about what they did to make the problem smaller;
• Ask children how they could adapt the puzzle to make it easier, or more challenging (for example through fewer clues, or being able to use digits more than once);
• Use one activity per week over a half term to encourage regular revisiting of the content (addition and subtraction) and strategies (working backwards/trial and improvement);
• Have children create their own versions and send them to us to challenge our followers - Twitter: @UKExceED