The Cambridge Science Festival is the national leader in its field, with over 100 activities and events spanning 10 days, April 18-28.  You can filter this year’s online schedule of events by age (family/teens/adults) and type (activities, workshops, performances, talks, other) or by date.  Some events require pre-registration or tickets.  Some are for educators.  The Science Carnival on Saturday, April 19, 12-4PM, has five themes:  Earth & Space, Micro-Zone, No Limits, Game Corner, and Robot Zoo!  It’s too much to keep in your head.  Download the Guidebook app and search for “Cambridge Science Festival 2014” to get your mobile guide to events.