Hey Trick,
The point of a thesis is to prove something using support. This isn't a persuasion though, because it isn't just a personal opinion. It's something that can actually be PROVEN not just "this is what I think". Don't use first person. For example, a good thesis could be "Malcolm X was an integral part of the Civil Rights Movement." then you go on with facts to prove why, as opposed to the unacceptable "I think he was good for Civil Rights and here's why I think that."
If I wasn't clear or you need more, post again and I'll give you more info.