A really badly written question can transform even a good math student into one who looks bad on paper some of the time, unless/until they develop the "Hmm, what they really meant was..." skills HowlerKarma was talking about. Kids who are having more difficulty are likely to mess those up every time. That clarity is SO incredibly important.
We ran headlong into the badly-written-word-problem thicket tonight:
"24 students wanted to watch candy being made in the firehouse kitchen. The students organized into even groups and gathered around each of 5 pots of candy. How many gathered around each pot? How many students had to stand behind another student?"
Err..huh? But then the groups weren't even, regardless of whether "even" means "number in group is divisible by two" or "the groups were the same size." That is, assuming that the remaining students were made to "stand behind" the others?? So they didn't count as being in the group??
Time and again, the edumacational system in this country manages to surprise even a cynic like me with the depths to which it will sink in search of mediocrity.