You may have keratosis pilaris. I suggest trying Dermadoctor KP Body Scrub. You can find out more about it here -
I had this problem a few years back. I started using Tend Skin and it all went away!
I also recommend not wearing any tight-ish or even fitted pants. Try wearing loose clothing on your legs for a while until it clears up. Any rubbing migh make take it longer to fo away.
You might want to get it checked out by a dermatologist first to make sure it's not something that could benefit by some sort of prescription. Blocked pores, for example, can create bumps that can be easily treated with medicine.
If it's not s medical issue, sugar scrubs (Sephora sells quite a few different brands) work really well, along with one of those net puffs which can be purchased in any discount store for about a dollar. The sugar scrubs will leave your legs feeling silking soft and help eliminate the bumps. There are other scrubs that are sold at Sephora for this purpose, too, but I've been pretty pleased with the sugar scrubs because they're very gentle.
Another possibility is that the bumps might be caused by ingrown hairs, from shaving. If that's the case, if you use a razor, make sure to use a fresh blade each time you shave for awhile. There are shaving creams that are sold to help deal with ingrown hairs. Ingrown hairs need to work their way out through the top of the hair shaft. A good shaving cream and a sharp razor can help prevent the recurrance of ingrown hairs. Waxing for awhile, or the use of a depilatory, will also help to eliminate ingrown hairs, as does laser hair removal.
Hope this helps.
Murad Acne Body Wash is a good product to use to get rid of body acne. You can read all about it at: http://sephora.com/browse/product.jhtml?id=P47517&
Just use it diligently and the bumps on your legs should clear right up.
I hope this helps you.