The annual Butler County Farm Tour is 10 a.m. to 4 p.m. Saturday. Farms and other locations will each have special activities and educational opportunities. The self-driving tour is hosted by the Butler County Tourism & Convention Bureau. Admission is free, but some stops may have additional fees. Visit www.visitbutlercounty.com/farmtour.

Children’s Museum, 10 Children’s Way, Allegheny Square, opens the 13th annual “Tough Art” exhibition Thursday. “XOXO: An Exhibit About Love and Forgiveness” will open Sept. 28. The Children’s Museum is open 10 a.m. to 5 p.m. daily, except holidays. Admission is $18 for adults and $16 for children ages 2 to 18 and senior citizens. Children younger than 2 are admitted free. Call 412-322-5058 or visit www.pittsburghkids.org.Heinz History Center, 1212 Smallman St., presents Vietnam War veteran and author of “The Things They Carried” Tim O’Brien for an evening program at 7 p.m. Wednesday. Tickets for the program are $20 for general admission and $10 for veterans, active duty service members and students. The History Center’s exhibition “The Vietnam War: 1945-1975” continues through Sept. 22. Visit heinzhistorycenter.org/timobrien.