XiaoXian,
i wouldn't say its wrong or right but urmm...but i believe you must be quite young only. If you say learning how to kiss, i put it as you have never kiss before and i mean french kiss. Firstly the most important thing is to protect yourself first, a guy who can volunteer to teach you how to kiss, to me i just think he is trying or might to take advantage of you. You'll never know after the trial kissing what he mights want to teach you next!!
Honestly for me i won't give my FIRST french kiss to a stranger who says he's willing to teach me, i sincerely believe to give your first kiss to someone whom you strongly have feelings for like your first love or boyfriend but definitely not to someone whom you have no feelings for and just wanna learn how to kiss the correct way.(that's my own opinion, not for anyone else), FIRST means there is only ONE TIME a FIRST KISS, at least must be a memorable, not when 10 yrs down the road people ask you who did you give ur first kiss to and you reply "some guy who volunteer to teach me how to kiss"!
Anyway i believe when the real time comes for the first kiss its just come quite natural, i really don't see why have to learn how to kiss with a stranger!!
Rgds