Then you must know how fast the body develops a tolerance to meth-like substances. They need more and more to get the same effect. That's a good way to condition them into becoming a well educated drug addict at age 15.
Then you must know absolutely nothing about amphetamines and other stimulants, specifically prescription stimulants.
Ask around on blue-light, erowid, and other drug forums about users of ADHD medications when they actually have diagnosed ADHD. If they don't move into recreational use, those low-level doses don't really cause tolerance issues.
And more importantly, any tolerance that is developed is simply the euphoric feeling that some prescriptions cause. Which, coincidentally, if an ADHD drug causes any kind of euphoria in a patient with ADHD, they have probably been prescribed the wrong drug for their specific case of ADHD.
How else do you explain, with proper dosing, the fact that, as you say "meth-like substances" actually causes people to calm down, when, for every other single human being most of us know, said stimulant will, wait for it, actually cause the typical stimulant responses.
They may be stimulants by nature, but they are prescribed for a very particular reason for clinical cases: they inhibit reuptake of NTs like norepinephrine, dopamine, and I think serotonin, and, in the case of amphetamines, they also induce the release of same NTs into the synaptic cleft.
For people who have normal levels, this would cause them to become very "stimulated".
For people who have some functional problem within those neurons, be it the production level of those or how well the receptors reuptake them, it essentially helps bring them to baseline.
When they are off of baseline, they may have any number of behavioral changes, depending on just what ratio of activation and production is happening in their individual brain (and consequently, this is why one stimulant like Ritalin may work better for someone, while amphetamines work better in others, and still others need non-stimulant drugs like Strattera).
When they are returned to baseline, they more closely resemble the normal behavior, which for them, is much desired and does wonders to help them accomplish what they need and/or want to do.
Baselines are established not out from the idea that, "well humans need to do this, so, that person is screwed up and a failure." Contrary to your beliefs, baselines are established based on neurology of not only humans, but also other animals. Most animals share the same neurotransmitters, and in general, the flow throughout the chain of events in the production and reuptake of most NTs is the same in both form and ratio.
The system of the brain is not radically different in humans from all other animals, the CNS is a fairly constant evolutionary development in the animal kingdom. Where humans differ is more in the amount of brain matter, the number of folds and just how much of the skull, and brain, is dedicated to tissue that is not directly involved in autonomous functioning.
This is a gross simplification, but it seems apparent that gross simplifications are necessary in this thread.
You may argue about how beneficial such abnormalities are, but it does not detract from the fact that the very point of the matter is that this abnormalities are very much obvious in neurological studies, and the abnormalities stand out not because of behavior, but because of the fundamental flaw in the flow of the essential chemical messengers in the brain, and in some cases, even the actual tissue structure.
There isn't any wiggle room, and only the willfully ignorant and those who want to justify their upbringing and demand everyone face all the challenges they faced would dare argue otherwise.
The fundamental flaw found in the brain that produces the symptoms of ADHD (regardless of what actually CAUSED that flaw), shares many, many similarities with anything ranging from Bipolar, Schizophrenia, Major Depression, General Anxiety Disorder, and, just because I want to stir the pot, the various types of behavioral addictions like gambling addiction and, yes, sex addiction.
To bring this back to the start, the key here is that NUMEROUS studies have consistently shown that, wait for it, long-term use of stimulant-class ADHD medications at therapeutic dose levels, have directly caused neural regeneration, neural growth, and even repair of malformed structures in the brain.
This has been readily observed through the various brain imaging techniques.
This is why they still continue to suggest that ADHD begins treatment in youth and, generally, can be cut once you reach adulthood. It is not that it is a childhood disease, as it is not; the long-term use simply has permanently changed the patient's brain for the better, it healed them of the disease. Successfully approached with therapy and the correct drug (which can take some time to figure out for each patient), it can be beaten.
The rising number of cases for Adult ADHD suggests that, if left untreated or undiagnosed in childhood, it does not in fact go away like some childhood issue.
Adult ADHD tends to take on a different form because these individuals have had years to tackle their problems and do everything they can to adapt so that they can succeed. These are actually great cases because they typically HAVE adapted quite well, but still struggle to truly grab life by the horns. It can still be treated, but it can take years of failure (even with significant effort) before they come to the realization that they should be reaching out for help.