This list is far from comprehensive. Check your local LGBTQ Center for organizations local to you and your school.
AAUP Website: Resources on Sexual Diversity and Gender Identity
GLSEN: The Gay, Lesbian & Straight Education Network – started by a small group of educators and currently the premier resource for research on national LGBTQ youth.
TransActive: A center located in Portland, reaching out nationally, providing holistic services to empower transgender and gender nonconforming children, youth, and families.
Trevor Project: Founded by creators of the short film Trevor. This national organization provides intervention and suicide prevention services to LGBTQ youth age 13-24.
Teaching Tolerance: Lessons about LGBT African American Civil Rights movement leaders:
OutHistory: Tells stories about the queer past, about people who identify as lesbian, gay, bisexual, and transgender.