wow what a breeding ground for OT discussion
first let me just say that be wary of any test at home drug kits as false results are common, and the truly reliable method is of course lab testing.
if you are a parent considering this for your kids i would strongly suggest trying to sit down and having a candid and non-threatening conversation before you jump to any conclusions or the such. trust is important in any relationship. if anyone, child or adult, is taking drugs they should understand the consequences, this goes for any substance, legal or otherwise. it is not the use of substances that are necessarily harmful, but rather the abuse of substances (think about it, the overuse and abuse of just about anything is harmful, even food and sex, basically the mind begins to obssess and that is where many problems arise). now clearly certain drugs have much greater potential for abuse, heroin and cocain are amongst the most addictive drugs, and can change brain chemistry even after single use, but this does not mean that there is anything inherently wrong with the person. i don't claim to be an expert, i don't think anyone here could, but i studied neuroscience, with a concentration on drug abuse and mental disorders, and have read a great deal about this subject area, so i have come to my own conclusions, which i can understand that not all would agree with (and those that may agree, may agree for other reasons). one of my fellow students and good friends had for a long time been victim to substance abuse, and while she saw many of her friends struggle with drug abuse, she eventually managed to escape it and in her 30s came back to college also studied neuroscience and is now going through medical school, and i would trust her more than some other doctors (or potential doctors) that i've met in my time. my point is substance abuse itself does not mean anything, does not equate to violence or irresponsibility or wasting away of the mind (not that these things don't happen, but that is to be judged on an individual basis, not by stereotyping). there are those that can control themselves, and those that lose control, that is what leads to abuse, and that is what people should focus on when trying to help each other. sending thousands of people to jail for drug use or possession does not help anyone and is a waste of time, money, resources and most importantly the livelihood of those imprisoned--we need to work better with each other to come to a better solution, but also realize that the drugs themselves are not necessarily the problem.
also, it's a bit silly to defend the government for its handeling of the issue of drugs since it is two-sided and has in the past introduced illegal substances into communities, not to mention that we have a war-mongering president who used to dabble in a little cocain (evidently even at camp david while his father was in office). although gw certainly is no success story for drug use and recovery considering he's run every organization he's ever headed into the ground (oil company arbusto, baseball team, and now the whole country, take your pick, economy, foreign relations, etc etc), but i don't blame the drugs for that