
Addition Digit Swap
Start with a threedigit addition. What digits are produced in the answer? Swap one of the digits for a new one to create a new addition. How many swaps are necessary to create all ten digits in the sums?

Addition Wheels
Arrange the digits 09 in three rings going clockwise. Using different diameter lines that go through the different digits, how many of the five additions total over 1000?

Opposite Digit Circles
With this island on addition, it takes a little bit to set it up but once you have done so, it’s fairly easy to follow and the patterns are quite surprising. It’s an example of when maths at first just…

Distinct Digits to 5555
This island focuses on the use of column addition and even though it focuses on only four digits, it promotes a trial and improvement approach that requires a lot of mathematical thinking as well as having the potential to naturally…