Is it normal that i really like my teacher?

So, me and my teacher (let's call him Bob), so me and bob have been talking friendly wise. I had him as a teacher last year and I made it into a club and he comes by and helps up with it, so I see him sometimes! During open house, I was assigned to stand near his room and hand out papers. Every time it was time for parents to leave for new ones to come, he'd stand with me outside and we'd talk about stuff and we'd joke around and things like that. He also notices it when im sad and he'll try to cheer me up again. Also, during homecoming dance, I was wearing a tight dress (not too tight, classy dress) and it was the first time he ever saw me dressed up like that. And as he was passing out food, I was walking up to him and as I looked at him, he was already staring at me (kind of at my body and then my face) and he looked away fast but then looked back at me because then that would've been obvious that he was staring at me you know? Anyways, long story short, I always fantacize about him, and I think I really really like him, but im obviously not going to show/tell him that. (Btw he's 27, im 16), is this normal?