Oh, and have her drink lots of water and cranberry juice - if she doesn't like the juice, they make cranberry pills that will clean the bladder very quickly. UTI has nothing on cranberries :) Maybe that will help with the odor/color. It sounds like her urine is just concentrated, nothing serious.
Has anyone checked her for bladder control. Goodness, I see commercials all the time for bladder control issues but can't think of any of them now. Has her doctor checked for that? I doubt she's being lazy, it must be embarrassing to wet at school and during the night. She's probably just given up and doesn't think anything will fix it.
If her doctor hasn't found anything, get a 2nd opinion... and a 3rd or 4th if necessary.