My daughter missed many, many days of school while in elementary school due to infestation problems. I tried everything (at least I thought so until I read this forum! LOL).
Our problem was that some of her schoolmates were not being treated due to "religious reasons"
Here is what I found as our effective and safe treatment-of-choice:
There is a device called the Robi-comb. It is available, or can be ordered from most drug stores. Runs around 30 bucks. Check with the pharmacist.
Here is how it works; it is a small comb, like a nit comb, but is battery-powered to zap the bugs to death when they contact the tines of the comb. It only takes 12 days, once a day, and the problem is solved.
It is chemical-free, the only disadvantage is that the kids will feel a little tingle when the bugs get zapped, but my daughter was willing to put up with that in order to keep her long, thick hair.
I think it would be great for clinic nurses to have Robi-combs available for use for kids whose parents do not seem to care enough to tackle the problem, for whatever reason. I know it is annoying and sometimes difficult to get rid of lice, but is necessary (at least in my opinion!).
Hope this helps someone!