In high school, I had my own web development company and was an accomplished, award-winning saxophone player but I struggled getting the grades I should have been able to get for a reason that I couldn't understand. I was diagnosed with ADHD in 10th grade and set upon a journey involving virtually every drug recommended for the disorder. I settled upon Adderall and have been taking it ever since. Reading through the comments on this page, I find it amusing that everyone seems to have such a black and white opinion on the subject. I, on the other hand, really don't know what to think.
Studies show that nothing is more effective at treating ADHD than stimulants and cognitive therapy does virtually nothing without drugs. Furthermore, people who control their ADHD with medication are FAR more likely to avoid substance abuse than if they leave their condition untreated. I'm sure everyone knows a really smart kid in high school who smoked their life away on weed and never made anything of themselves. I know that I personally would have probably gone this route, as I was already heading in that direction. Finally, stimulants like Adderall haven't been shown to have any real long term health consequences and (contrary to popular belief) are not particularly addictive if taken as directed.
Anyone who has been to college in the past decade can tell you that Adderall can certainly help you cram for tests. Does that mean it gives them an advantage? I really don't think so. I've crammed for a lot of tests, and unless you're a business or mass communication major, you are not going to get an A by cramming. Try cramming a month's worth of organic chemistry in one night with some Adderall. You'll probably pass, but you definitely aren't getting an A. People get A's on tests by keeping up with the work. Not to mention the horrific day you have after cramming all night on speed. The biggest advantage I saw with Adderall was playing Quake 3, and even then there were people a lot better than me that used nothing but Mountain Dew.
I guess what I'm saying is that I think that people are overestimating the power of stimulants. Their biggest advantage is that you can stay up later, but if you don't take the drug regularly, you will also not be able to get to sleep. You'll also not eat enough and will probably have issues with sexual dysfunction. If that sounds like an unfair advantage to you, I don't know what to tell you.