There's a shampoo called Lice Guard (there's also a leave in spray). It's going around my daughter's classroom and the teacher has recommended it. She's using it and so far she hasn't gotten lice, even though it's been going on since the January.
I got some tonight. Another kid went home with lice today, I just do not want to deal with it. My daughter has waist length hair, I can't imagine having to comb through all that with those tiny combs. I've been washing her hair with some mint/rosemary/tea tree/lavender shampoo and conditioner, spraying a waxy product in it, braiding, pinning up, and covering with hair spray.
They've also banned bows for girls and made them start putting their jackets, hats, scarves (not that they're using them a lot, it's March in Louisiana), and book bags in those huge Zip Lock bags, same with their rest mats.