If you have discovered that (UGHH!!) one of your children has come home with head lice, then finding an effective natural lice treatment should be the next thing on your mind.
I haven't ever treated my kids with commercial head lice treatments as I have heard nothing but horror stories about treatments that don't work, and are expensive to boot.
Not to badly reflect on any particular brand of head lice treatment, but my opinion is, why use chemicals when you can effectively get rid of lice naturally?
By the way lice are attracted to clean hair, and are a constant problem in schools, so don't take it personally even though there is a certain amount of stigma and shame attached to them!
You can tell that your child might have head lice if their head is itchy, and upon inspection you can see the adult lice (a bit like a flea), usually behind your child's ears and towards the base of their scalp.
This method works by the oil coating the lice and their eggs and essentially suffocating them. Have your child up on a high chair or somewhere where you can reach all parts of their hair. Place the old towel around their shoulders and slowly add the oil one section at a time until their whole head is well soaked.
Once you have finished, wrap their head in glad wrap or with the shower cap and leave it on their head for at least two hours. They can even sleep with it on and then rinse in the morning. This is one time when a DVD comes in particularly handy to distract them from having to sit still for so long!
After the soaking period rinse their hair with vinegar, this helps to loosen the glue that the lice use to stick the eggs to the hair shaft. Now wash with detergent, this cuts through the oil (that is what detergents are designed to do- dissolve grease!) After this they might need one or two more normal washes with shampoo.
Now for the final step, again get your child somewhere comfortable and section by section work through their hair with the lice comb. Make sure you have good lighting, the nits are kind of reflective in bright light and will be much easier to see. All the adult lice should be dead, but eggs/nits will need to be removed carefully, they should be easier to get because of the vinegar loosening them off the hair.
Once your child's head looks clear of lice its time to attack you house. Boil all combs and brushes, again you can add some tea-tree oil to help repel lice in the future. All toys can go in a plastic bag for two days, seal tightly until adults and eggs have died. Wash hair ties, scarves, hats, pillow cases and bedding and put in a hot dryer for 20 minutes. Vacuum your couches, put all cushions in a sealed bag as well for a couple of days, don't forget car seats, or anywhere else that your child's head has been in contact with.
To be sure that you REALLY have got rid of them all, continuously check your child's head, after the first infestation, you'll know what the nits look like on the hair shaft. I usually will redo a full treatment with olive oil 1-2 weeks after the first to get any nits that we might have missed in the first treatment and prevent any new eggs being laid.
Be vigilant for 2-3 weeks, as this is how long it takes eggs to hatch (8 days) and grow enough to be able to lay their own eggs. Getting rid of lice properly the first time will mean they will be a pain for maybe a week or so, if you don't get rid of them properly they can plague your family for months on end!