8. Have We Had a Class Together? I Could've Sworn We Had Chemistry

If your crush doesn't even know you exist, you need an opening line, and this one takes the cake.

Approaching someone to talk about a class won't look strange at all, and if he seems sweet, you can follow up your question with the second half of the line in order to finish hitting on him.

I Thought Happiness Started with an H. Why Does Mine Start with U?