As an assignment, they are basically wanting you to state a thesis argument or claim that fits into the subjects you've chosen. While I can't write your assignment for you, I can give you some topic suggestions that fit into the category of freedom and/or equal rights to get you started. Keep in mind, you may not agree with the position that you are arguing in your speech.
1) Gay Marriage - you can state a claim either for or against the right of homosexuals to marry, framing it either as a question of equal rights with heterosexual couples or as the right of straight couples to have marriage defined and protected.
2) Immigration - one could argue that immigrants, legal or not, should have equal rights in the workplace for minimum wage, limits on working hours or protection from unsafe working conditions. You could also argue that people should have equal rights to seek jobs and better, safer conditions for their families.
3) The Westboro Baptist Church - this is the group that protests funerals for American soldiers killed in war as being punishment for America tolerating homosexuality. There was recently a Supreme Court case about this, and you can ether argue they have the right to free speech or that this should be restricted.