Mine was when I was in eighth grade, I remember it very vividly.
I was 'dating' a seventh grader at the time, both of us being in junior high school, and we had the same lunch together, thus how we met.
About 5 days in, I was in my shop class which was my last period, and got a text from her telling me to meet her at the BACK of the school near the art room before I left.
Of course, this being a long walk I was like "Nah, not worth it", then she texts me back saying she wants to 'kiss' me and stuff.
Me being an eighth grader, immediately decided it was indeed, a good choice to go back there.
So I met up with her and we had quite a long kiss '~20 seconds', and then I left.
We ended up breaking up a week or so later.