NSF offers a wide variety of paid summer research experiences for undergraduates. To search over 600 programs, please visit: http://www.pathwaystoscience.org/undergrads.asp

For summer research specifically in ocean sciences:
http://www.pathwaystoscience.org/oceanscience.asp

For summer research specifically in engineering:
http://www.pathwaystoscience.org/engineering.asp

For mentoring and professional development support, please take a look at AGEP alliances:
http://www.agep.us