Two dice are rolled. You add up the spots on both of them - that is the sum.
Every roll appears in the table exactly once. The left die sits on the left edge, the right die on top, and each square holds their sum.
The left die and the right die are two different dice. That is why 2 + 5 is a different roll from 5 + 2, and both of them count.
Find a sum in the table and count the squares it stands in. That tells you in how many ways it comes up.
Some squares are empty. Fill in the sum there first, then start counting.
Example
For parents
What does this exercise practice?
This is where thinking in possibilities begins - the classic way into probability, but entirely without fractions or percentages. The child counts how many ways a result can come about at all and discovers that not every sum comes up equally often. Searching row by row and column by column is worth just as much as the answer, because anyone who tries at random always misses one possibility.
Common pitfalls
The most common mistake is counting 2 + 5 and 5 + 2 as a single roll. Then the 7 ends up with only half its ways. The table prevents that, because both rolls stand there as two different squares - one to the left of the square with the two equal faces, the other to its right. The second stumbling block is assuming that big numbers come up less often than small ones. The 4 and the 10 come up exactly equally often, three times each.
How to practice at home
Roll two dice together and make a tally mark for every sum on a piece of paper. After thirty rolls you will see which sum has the longest tally. It is almost always one from the middle, and next to the 2 and the 12 the paper stays nearly empty.
Related: Multiply the Dice, Combinations