Choo-choo! Little kids love trains so much, there’s even been research to discern why. Some scientists think it may have to do with the male brain (since the train-obsessed are often boys); others point to how the motion and speed of a train stimulates children’s brains. Whatever the reason little ones love locomotives, they can indulge their fascination at the Great Train Days at the Children’s Museum of Sonoma County in Santa Rosa. Kids can build their own train tracks, dance to train music, and even take a ride on a Live Steamers train. There will also be a chance to look at model trains and talk to local train experts from the Redwood Empire Garden Railway Society and Coastal Valley Lines. The event will be held July 22–23, 10 a.m.–2 p.m., and is $20, or free for infants 11 months and younger. Discounts are available for seniors, members of the military, and MediCal, EBT, and WIC beneficiaries. Find out more at cmosc.org/events/the-great-train-days.