Why does he act so weird around me?

There’s a guy. I’m 21 and he’s in one of my classes. I can’t tell if he’s interested in me or not. We all sit in a circle and it’s an English history class so we talk about race issues and stuff like that.
He usually chooses to sit across from me and always makes eye contact with me specifically while talking to the class.
He’s close with this other guy in the class and they’re relationship is a little weird they always compliment each other but the other guy is married to a woman.
The guy I’m interested in has a long distance girlfriend but he basically said that caused problems for them one day.
Whenever he’s talking in class his eyes usually focus on me and he’ll make long term eye contact with me it’s awkward sometimes. I honestly assume he’s just zoning out or something lol but he does it often. Once I tested it and made a weird facial expression and stared at me in shock so he’s aware he’s looking at me.
He had to move seats class last because someone stole his seat so I wasn’t rlly in his eye line so he kept making eye contact with someone else while talking but he still glanced at over at me
He tried to talk to me once before class about how it was nice to have a break
Once before class, he was having a funny debate with another classmate about a character. While they were debating he kept looking at me and he was smiling ( I don't know maybe because the argument was funny ) but he kept smiling and looking back at me so I smiled back. I smiled at him and looked down and raised my eyebrows ( which is kinda obvious )
And I looked back up and we made eye contact which means he was looking at me and he said something and then put his head on his desk.
Also once I was outside the classroom and we made eye contact when he was walking out the class.
Is he interested?
Why does he act so weird around me?
Post Opinion