"What should I take?" threads are against the rules, so I'm going to have to close this, please read the BL User Agreement and the forum guidelines for any section you choose to post in if you haven't done so already.
I'd agree with others that 14 is too young - the earlier you start expanding your drug career the more it tends to escalate later on in life i.e. you say you won't use crack or heroin but pretty much every person who's ever used either/both said that initially - that's not to say you will, but if you start trying more drugs now you'll get bored of them a lot earlier on in life and be more likely to be drawn to those kinds of drugs. Take it from someone who originally was anti-drugs, then "would only ever smoke weed and try psychedelics", and now has consumed almost 100 different psychoactive substances in just 5 years using drugs.
The main reason I'd advise not trying these things at 14 though is particularly in the case of psychedelics, they're not just something you take to get a little stoned like weed, but a single trip can be a serious life-changing event for better or worse. Psychedelics are pretty serious and deep drugs, and should be respected as such. Don't get me wrong, they're a whole lot of fun too, but you'll get a million times more fun out of them if you respect them for how powerful they are.
Since psychedelics play on your subconscious mind and a lot of your past experiences play into what you'll experience during a trip I think the more you grow and mature the more you'll be able to get out of the experience, and the more enjoyable on the whole it'll be. Since your first psychedelic experience, or your first few, are usually the most memorable, that means that you don't want to waste those experiences by having them so young when they won't be quite as deep or meaningful as they could be in a few years time.
Personally I tried psychedelics at 17 and while I'd have been happy to have tried a lot of other drugs at that age, it was too early for me, and I regret not waiting at least another year or two, maybe even more.. The experiences were wonderful but I can tell if I'd first tripped even just a year later my first experiences would have gone a lot deeper and been more interesting.
As far as MDMA goes, yeah you'd have a great time even now but someone seriously if someone offered me $1000 to go back in time and try MDMA at such a young age I'd tell them to go fuck themselves, I can't imagine wasting my first experiences with the drug so young. MDMA quickly loses its magic (for some people seemingly permanently) if used frequently, and if abused it can also cause a lot of very bad long term damage - so if you must take it, make sure you're rolling once a month at absolute most, even that is really pushing it and the accepted number among people who've been doing it for many years now is usually more like 3-4 rolls a year to avoid any problems and keep the experience fresh. I wouldn't advise taking it so young though, wait a few years and again you'll get much more out of the experience as with psychedelics.
Personally I wouldn't even want to be smoking weed at 14 since I found after a few years weed got pretty boring for me and now I don't enjoy it as much as I used to - it's still a great drug but only once in a while and I can't enjoy it frequently like I did a couple of years ago. For what it's worth I'm only 21 now and only started smoking when I was 16, so it got old pretty fast.
That said if you're going to do anything, weed's probably your best bet. Just be careful - I'm sure since you've started smoking you've realised a lot of what they told you in drug classes was absolute bullshit and it isn't as bad as they like to make out, but one of the old favourite stories that weed can make you mess up school is damn true - most drugs + school work don't mix very well and I'd stick to smoking at weekends, because I witnessed myself just how quickly your education can go to shit when you're smoking every day.
Smoking just becomes more of a priority than your work, your short term memory goes to shit which impedes the learning process, you forget to hand in work etc, might even skip class to get stoned - keep it to the weekends and it's a lovely nice wind down after a long week but these next few years of your life shape who you'll be for the rest of your life so don't screw up!
Anyway since these types of threads aren't allowed, I'm going to close this. If you wish to open up a thread again discussing whether you should trip at 14 that's within the rules, but you're not really going to get much else in the way of answers other than what's already been said.
Closed.