Sciencekid, I suggest you just google "lenticular clouds". I did, and my first source,
Wikipedia, contains quite a lot of information on how these clouds form. And
this site contains information on how lenticular clouds have been mistaken for UFOs. Really, there is a lot to find if you only google!
Can't resist showing you this picture of a long string of lenticular clouds. Don't they look gorgeous? According to the Wikipedia site that I linked to, these are an example of a lenticular version of a
wave cloud.
Do look around on you own! There is so much to learn out there. But remember to always quote your sources, and never present other people's texts as your own!
Good luck!
Ann