My spanish teacher is hitting on me!?

And I think its kinda weird because this teacher is supposed to be gay. He stops me every time we see each other in the hallway and asks about my life, which doesn't bother me, but he can get kinda creepy at times. Like this one time he asked me what I was doing over summer break and I told him I was going to my family's beach house and he was like "oh, that's cool! You should send me some pics!" I'm hoping he meant pics of the ocean and lighthouses and stuff... Since I was standing with friends I just let it go, but it's kinda weird for him to ask that. I'm in the marching band and sometimes he will sit in his car and watch me the entire practice. Another time my spanish class went on a field trip to see a play and my bff and I had to sit across from him. When my bff fell asleep he started talking to me and after a while he told me he couldn't hear me so I should sit in his seat. i went and talked to him, and while we were talking he kept looking down at my skirt. He eventually caught on that I saw him looking and told me that my skirt was very beautiful and sexy. Then he started touching it and that got kinda awkward. The next year, he chose only my class to go on an overnight trip and he did a room check every night. But all the kids in the class and my friends I roomed with for the trip have told me that ours was the only room he went in. And he happened to come in while I was taking a shower, so he opened the bathroom door to ask if it was really me and to make sure I wasn't off in another room. In class he looks over all of the students shoulders at their work, but he always touches my shoulders, arms, and back when he looks at my work. Other teachers and students tell me he never stops talking about me. I guess he is just trying to be friendly and make a friend because all of the students think he's weird and won't talk to him. How should I get across to him that he needs to tone down the flirting but still sound nice? I don't want to come off as rude...