Two groups have means of 14 and 18. Is four a lot? Nothing about that number answers the question until you know how much the data varies anyway — and that is the whole of this sheet. These free printable worksheets ask for the gap between two centers measured in the sets' own spread.
If they get stuck
The answer key prints on a separate page.
Every pair on these sheets has the same mean absolute deviation, and the sheet says so at the top. That is not a simplification, it is the condition the standard names: two distributions can only be compared this way when their variabilities are similar. With one shared MAD there is one unit to measure the gap in, and the answer is a whole number of them.
The work is three things and the answer key prints all three: the mean of A, the mean of B, and the difference divided by the MAD. A child who stops after the subtraction has done the arithmetic and not the comparison — the difference is a number about these two sets, and the multiple is a number you can carry to any other pair.
One question from a sheet like this one, worked a step at a time — with a sentence saying what just happened and why.
Comparing two data sets, step by step