The San Diego Union tribune has a feature article on why kids don't ride their bikes to school anymore. Article
among reasons cited are fears about traffic and abductions, which are totally unfounded.
From the article:
A Caltrans survey in 2001 found that children made 74.3 percent of all trips by car, 15.2 percent on foot, 7.5 percent on school bus and 1 percent on a bike. In San Diego County, 62,500 students – about 12.5 percent of all students – rode school buses in 2002-03.
In a 2002 national survey, 71 percent of adults who responded said they walked or rode a bike to school when they were children, but only 22 percent of the poll's respondents said their children walk or bike to school now.