Is my guy friend coming onto me?

I noticed that when me and my guy friend hangout alone he treat me differently when he is with his other friends. We don't have the same friend because I am a year in college ahead of him. He would joke with me, put his hand next to me, give me the look, doesn't acknowledge me when I'm with my other friend except if I'm alone, sing to me when were alone, fidget around me, hover over me, etc.