Two keys to successful parent involvement in fighting drug abuse are cited by Marjery Ranch, executive director of Parents Who Care, and others in the movement:
1. ''No blame. Parents shouldn't blame themselves because their children are experimenting with drugs. School authorities shouldn't be blamed. Police shouldn't be blamed. No one needs to accept blame because it's not important. School administrators and police are willing to work with us because we don't drop responsibility in their laps. We're willing to work on a cooperative basis.''
2. ''Youth involvement. Peer pressure is the thing, even when it is just imagined - as it often is. Only others of their own age group can convince kids that they do have a choice between alcohol or other drugs and something else.''
The major challenge, says Mrs. Ranch, is ''to keep the movement going. Because families 'grow out of it,' you have to keep recruiting and educating new parents.''
Parents Who Care had its inception in the living room of a home in Palo Alto three years ago. Today it is a nonprofit, public-interest corporation with more than 40 chapters in the six Bay Area counties. Parents from as far away as San Diego have been helped in forming their own groups, though most are not formally affiliated with PWC.
Some 500 parents from Palo Alto and surrounding communities attended the first public meeting in Palo Alto, Mrs. Ranch says. Since then it has ''put on presentations before at least 75,000 people,'' she adds.
Mrs. Ranch notes that there were some 300 parent groups in different parts of the United States in 1980, when the National Federation of Parents for Drug-Free Youth (NFP), an umbrella organization in suburban Washington, D.C., was formed. A year later there were some 800 groups, and by the time of the NFP national conference last October, more than 3,000 local organizations had been identified.