April 20–29
Science festivals in Philadelphia and Cambridge, Mass., both include science carnivals with games, plus check out video game-making in Cambridge and Astronomy Night in Philly. See bit.ly/fairCam and bit.ly/fairPhilly
April 28–29
Meet Bill Nye and the hosts of the TV show MythBusters at the USA Science & Engineering Festival in Washington, D.C. See bit.ly/fairUSA