Her use of mousse may be causing this problem. Mousses tend to provide only light hold, and so a person needs to use a ton of it in order to get any kind of control, leading to the dreaded "crunchy head." Additionally, many mousses contain drying alcohols, which could make the problem even worse.
I would suggest that your daughter try a strong gel instead, so that she can use much less of the product and get the same control she wants. Try LA Looks Sports Gel, or Biosilk Rock Hard Gelee (don't be afraid of the "rock hard" in the name, it will not result in helmet-head). Apply the gel in sections to all parts of the hair when it is wet, and then don't touch the hair until it dries completely. The hair will be hard at this point. Then, scrunch the hair in firm motions until the hair is no longer hard. Let us know if this works!