Katie is not cheating. From the question, it sounds like Katie's spinner is 1-12. James has two dice so he has two sets of each number 1-6. This means that Katie can roll two numbers greater than six but James can only roll up to six. Using probability, I think there is a 50% chance that Katie's number will be bigger than James every time she spins. A fairer way would be for them both to play with the same dice or spinner.
Simply present that you would split them up as a factor of two. ( make two lines going either vertically or horizontally. place in varriations, a marble in one line and a marble in the other and then count the leftover
