Kids can create ramps, jumps, slides and demolition derbies for their toy cars at the third annual Extreme Hot Wheels event Saturday and Sunday, Aug. 11-12, at ScienceWorks Hands-On Museum, 1500 E. Main St. Local rat-rod, hot-rod and street-rod racers will be at the event with their rides. ScienceWorks is accepting donations of old Hot Wheels sets, tracks and cars. Museum hours are 10 a.m. to 6 p.m. daily. Admission is $7.50, $5 for children ages 2 to 12 and adults older than 65. See www.scienceworksmuseum.org or call 541-482-6767.