I like the idea, pass out flyers against child abuse and mention both DARE and NAMBLA. By equating the two in the minds of the public, plus the added bonus of having the "Miller Newton touched my junk" thread printed on the back of your flyer in glow in the dark ink, you will help create the (correct) perception that DARE is as dangerous to kids as NAMBLA. Use words like "Organizations which promote child abuse, such as DARE, NAMBLA, and The Miller Newton Foundation for Decency......".
I also like the idea of narcing them out, but I wouldn't use a white powder, it could get you called "bio-terrorist". Use aspirin and oregano instead. Better yet, just get their tag #s, pay a detective (or Richard B)to find out where they live, then call in an "anonymous tip": you heard a couple arguing about the car and feeding of their meth lab. Tell them you saw dirty naked kids wandering around in the mud in the front yard, drooling, and disoriented.