These girls admitted as such and laughed about it. My DS was also accused, by a small group of 4 girls (who were 4 of a larger group of around 6/7), of hitting all 4 of them. My DS, at the time of the alleged attack, was in his room talking on Minecraft, with the DS of a family friend. I know that because I could hear DS upstairs, while I was tidying up in my room a few feet away. So he was nowhere near these girls.
The teacher that was accused of rape, at the time the young girl said he had raped her, was at my friend's house having dinner (both he and my friend are long-time childhood close friends, and grew up together). Besides, I know from many parties at my friend's house, that this teacher is very much in love with his wife, and is not interested in anyone else (if you saw what I saw, you'd be saying the same thing.........that he's smitten with his wife). The young girl's story was totally proven to be false, and I know that because I spoke to said friend on the phone at the time the alleged rape took place, all while the teacher was in the same room as her, saying hello to me, and my friend was relaying his message over the phone. Everyone who was in the room at the time, and others who had been on the phone to my friend, all spoke to the police about where the teacher was at the time of the alleged rape. It turned out that, only a few days earlier, the young girl had her advances turned down by said teacher, and she seemed to take it hard.
It took those accusations for DS to want to have nothing to do with females in general.
As I said, I can only teach him that there are a few women/girls that will make those accusations up, but those couple of incidents are enough for him to be put off girls for the foreseeable future. He's happy to go his own way, and I don't really blame him.
You know the old saying "Once bitten, twice shy".