LEGOLAND Discovery Center is celebrating the 40th anniversary of the LEGO Minifigure on June 21 with a super-sized Mini BrickFactor build-off competition. Kids ages 5 to 15 can enter to show off their creative building skills for a chance to win a one-day apprenticeship with the Master Model Builder. The competition takes place in two rounds – mini division (ages 5 to 9) from 9 a.m. to 12:30 p.m. and junior division (ages 10 to 15) from 1 p.m. to 4 p.m. Located in front of the attraction just inside Grapevine Mills, the build-off is free and open to the public. Pre-registration is required by June 11 at dallasfw.legolanddiscoverycenter.com.