Anyone who disagrees with that has a very juvenile outlook on life and responsibility. Its also utterly naive to think there is a difference, mentally, sexually or intellectually between men and women. I can guarantee you, they think about sex just as much as we do.
This is where you are wrong. It's been shown time and time again in many studies that to men sex is just a physical activity and to women it's mental and emotional. Like it or not we are very different, most are polar opposites. Yes some women can be a little "looser" than others but the vast majority arnt.
The difference you wanted but can't seem to grasp... We all think of sex, a lot! But men are willing to act on most, any if not all those thoughts. Women (most) are willing to act on very few of them.
As for this situation, it would not affect the kid mentally except for the depression from not getting any more tail from that hot piece of cheerleading teacher now that they've been caught. A upper teenage guy isn't going to look at a hot early/mid 20s teacher as anything more than (physical) T&A and a fun time just like any other girl at school. As far as predatory goes. If it were me in that situation I would be the predator simply cause I would be trying my dangedest to get in her cheerleading outfit long before she ever had a chance to come on to me.
Now I'm not saying it's right for teachers to sleep with a student by any means. But as the student I dang sure wish I was in that exact same situation when I was in HS.