We've compiled a list of summer research programs, in many different fields of chemistry, biochemistry and biology, for sophomore and junior students interested in participating in an extramural research project. Note that most of these positions have deadlines of Feb 1 or March 1; thus it's important to get an early start on your job search. These positions are quite competitive; you should apply to several programs (not just a few) to assure being offered a position. It's also a good idea to get your applications materials to the institution in advance of the deadline, since some programs consider applications as soon as they are received.
Note that not all REU directors send us updates; therefore even if a program listed here is out of date you should still check it out because most programs run annually.
Here's a link to "Landing an Internship" from the folks at Academic Superstore.
These sites have lists of opportunities similar to this one:
Opportunities are listed by category; each is followed by a list of links to the specific site that describes the summer program. Locate your field of interest in the box on the left to search for summer research programs of interest to you.