Use a little creativity and do a little homework of your own to introduce diversity into your lesson plan. Teaching English? Dedicate time specifically for LGBT authors. Are you the drama instructor? Mention actors that are kids of gays, such as Anne Heche, Dorothy Dandridge and Judy Garland (more kids of gays). Teaching Math? Talk about the national origin of famous theorists then work that into a discussion about gay rights in that land (see gay life around the world).
If you're smooth enough few may notice that you started out talking Socrates and ended with the Stonewall riots. Indirectly, you're aiding them in seeing LGBT people as positive contributors to society.
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