My crush have a crush on our teacher?

I like a boy in my class. We are friends. I bet he knew that I had a crush on him. He didn't’t have any girl friend- as far to my concern. So it is cool there, but lately there was something happening, and I am getting green-eyed over it. He is getting kinda close and cozy with our class teacher. Eww, rite? I don’t know, but I don’t feel good every time I see him talking and getting all friendly with her. She is kinda young for a teacher, I don’t know for sure- but I guess she is in her mid 20-s. Before this, I don’t hold any grunt or hate towards our teacher, so does now. But I just feel sad and all jealous. This teacher is kinda attractive even though she is quite chubby, she is popular amongst the students, friendly, and has many students’ fans. Emm. Back to the story, does my crush have a crush on our teacher. He always tried to be close to her and sit beside her whenever the other students surrounded the teacher. And today, the teacher is wearing a new ring. So everyone is curious either the teacher is getting engaged with someone or not- and secretly I wish she did. And another not a so good news to me- she wasn't’t, it just she just found the ring while she was doing the house keeping. And some of the girls and the boys asked her permission to try on the ring, as always she didn't’t mind. So, the last person getting the hold of the ring was my crush, and suddenly the teacher teased me and asked the boy to put the ring on my finger, but he didn't’t have any respond towards the teacher’s words. It seemed like he didn't’t hear it at all. And the worst thing, I noticed how he looked at the teacher while the teacher was looking to me, (some of the other students were there and some were just chit chatting with each other- as the teacher just entered the class to release for the other teacher who was late to the class), and out of nowhere- my crush asked the teacher permission to put the ring on her finger, the teacher was hesitating(to my eyes) but as she was miss-so-friendly and all that, she finally gave up and let him to place the ring back on her finger. Oh my gosh, I am so jealous towards her. I know I shouldn't’t. But I couldn't’t help it. My questions are: does my crush have a crush on our teacher. 2. How could I get rid of my jealousy towards the teacher, I like her but in the same time I kinda starting to hate her.