A pipeful for kids who are curious about pot--who ""want to know what happens"" and, clinically, why, including the potential dangers. Testifying is suburban ninth grader Paul who, with two friends, reacts against parental abdication (permissiveness, preoccupation with getting ahead, reluctance to face the drug problem) and, influenced by the example of older kids, by disgust with the hypocritical status quo, tries marijuana. The experience is different for each of them (Paul sees more keenly, Charlie eats ravenously, Tom laughs and cries) but the gamut of their reactions is familiar to Charlie's doctor father whom Charlie and Paul, disturbed, consult the next day. Because his explanation jibes with their experience, because his pointers are practical (i.e. the consequences of drug-induced overconfidence, and especially the difficulty of determining dosage, the chance that marijuana may be laced with LSD), the boys are impressed and decide to go slow. And there's the affirmative aspect--doing something instead of copping out. Of the several juveniles based on the dope problem, this is the most relaxed, sensible and informative; with no pretensions to scope as fiction, it gets inside the youngsters sufficiently to make their predicament credible. And it's well-conceived for practical purposes--brief, easy to read, adult on the outside, elementary within.