Should I coach the boys to lie?
That does not sound good. Why would you want them to lie?
I think that they will bag more girls this way.
Regardless of the reason, I do not think that you should train them to lie. It is gross that you are thinking is such a barbaric manner.
They are just small little lies. What's the big deal?
Even little lies are wrong. They make people feel betrayed and make it hard for people to trust after being lied to.