I am looking for a site or service that allows people to rate and
comment on their experience at any of the many conferences,
educational programs, trips, tours, etc that are constantly being
offered by various groups like Close Up and Presidential Classroom.

Jmhines123,

I did some quick searching and didn't find a site that meets your
needs, but perhaps this info will help you a bit, or at least help
another researcher figure this out for you.

Enrichment
http://www.raleighcharterhs.org/enrichment.htm
--Doesn't allow outside commenters, however, provides short blurbs on
a whole variety of these kinds of programs, including CloseUp,
Presidential Classroom, National Youth Science Camp, etc.

Close Up Foundation:  Testimonials
http://www.closeup.org/testimonials.htm

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SEARCH STRATEGY

"close up" "presidential classroom"
://www.google.com/search?num=100&hl=en&lr=&ie=UTF-8&oe=UTF8&q=%22close+up%22+%22presidential+classroom%22&btnG=Google+Search

"close up foundation" testimonials
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF8&q=%22close+up+foundation%22+testimonials

***

Good luck in your search!

>Librarygopher

This looks like it potentially could be the sort of thing you're
looking for, but there aren't very many ratings and it is limited to
environmentally oriented programs.
http://eelink.net/studentprograms.html