A hard-line guide for parents primarily--combining strong evidence and dubious methods. Mann, who has written copiously on the problem, feels intensely that the effects of marijuana abuse--physical and otherwise, on society and individuals--are being ignored or downplayed by parents, children, the media, and authorities. To show the dimensions of marijuana use, she describes crises in the workplace, the armed forces, and schools--workers, soldiers, and students incapacitated by daily marijuana use. She goes on to proven and suggested health hazards: damage to the lung and heart similar to the effects of cigarette smoking, as well as damage to reproductive capacity, the immune system, and brain function. (Some studies now indicate changes suggestive of early senility with heavy marijuana use.) Mann includes many very early, still tentative findings, and dismisses any legitimate medical use of the drug. In all of this, she is not far wrong--but she does hector. And the efforts to combat marijuana use she praises--some ""tough love""-type parent programs, the Reagans' anti-drug utterances and initiatives (Nancy Reagan's ""sincerity, her concern are obvious. She minces no words"")--are the sort of thing that made marijuana a political issue in the first place. A more balanced and practical view for parents facing these questions is Robert DuPont's Getting Tough on Gateway Drugs (p. 670), while Stephen J. Levy's Managing the ""Drugs"" in Your Life (1983) will help a family establish an overall frame of reference.