The first-ever National Bike to School Day took place on May 9, 2012, in coordination with the League of American Bicyclists’ National Bike Month. Almost 1,000 local events in 49 states and the District of Columbia joined together to encourage children to safely bicycle or walk to school.

The event builds on the popularity of Walk to School Day, which is celebrated across the country – and the world – each October. Many communities and schools have been holding spring walk and bicycle to school events for years. National Bike to School Day provides an opportunity for schools across the country to join together to celebrate and to build off of the energy of National Bike Month.

Bike to School Day 2016 is scheduled for May 4.
Mark your Calendars! The Bike to School Day date for 2017 has been set:

Bike to School Day 2017 – May 10, 2017

Source: Walkbiketoschool.org
http://www.walkbiketoschool.org/ready/about-the-events