In case you hadn’t heard, you don’t have to pay hundreds for your next pair of glasses. Check out Zenni Optical at zennioptical.com. I don’t know how they make the glasses for so little, but I am sure grateful! Complete glasses start at $6.95 (as of Nov 2011). “Complete” means: frames, 1.57 lenses (these are really thin), UV protection, lens scratch protection, a hard case, and a microfiber cleaning cloth. For an additional $5, you can add an anti-reflection lens coating or a tint, making prescription sunglasses!!! They can also do bifocals.
Another nice feature on the website is the ability to upload a picture of yourself so you can virtually “try on” different pairs. Pay attention to the frame width, though. It isn’t easy to see if the glasses will fit just right. I made sure I purchased glasses with similar measurements to what I had before. Typically there is a flat $4.95 shipping charge for your entire order. Right now Zenni is offering free shipping on purchases over $50.
All the information you need to order glasses is on your prescription, except your PD (Pupillary Distance). Zunni’s website has a tutorial on how to find your PD, or you can get that information from glasses fitting at your doctor’s.
One additional piece of advice, I would not necessarily recommend purchasing glasses from Zenni for your child’s first pair of glasses–in case there is anything wrong, your child may not know the difference and you wouldn’t have the convenience of getting advice from the doctor. Also, Zenni doesn’t presently do lenses with prisms.
My experience has been that these are high (enough) quality glasses! Better quality than the inexpensive glasses I purchased from the doctor. My first pair from Zenni had the wrong prescription though, so mistakes do happen. Since then, I have not had a problem getting my glasses just right.
Savvy Chic 
I recently discovered GlassesShop and I wish I had known about them before school started this year. It is really a good store.