Harmony Museum, 218 Mercer St., Harmony, offers guided tours from 1 to 4 p.m. daily except Mondays. Admission is $7 for adults, $6 for senior citizens, and $3 for youth ages 6 to 17. Call 724-452-7341 or visit www.harmonymuseum.org.

Carnegie Science Center, North Side, presents Lionel Days, a monthlong festival of trains, through Jan. 1. The centerpiece event of Lionel Days is Locomotion Weekend, this Saturday and Sunday, with a rail yard filled with guest train displays by local hobbyists. Visitors can bring their own model trains for a free checkup by the “Loco Doctor” and enjoy themed activities. The railroad is free with general admission, which is $17.95 for adults and $11.95 for children ages 3 to 12. Call 412-237-3400.Phipps Conservatory and Botanical Gardens, 1 Schenley Park, presents the winter flower show from 9:30 a.m. to 11 p.m. The winter light garden runs from 5 to 11 p.m. Admission is $15 for adults, $14 for senior citizens and students, and $11 for children ages 2 to 18. Call 412-622-6914 or visit phipps.conservatory.org.Children's Museum, 10 Children's Way, Allegheny Square, will be closed Dec. 25 and Jan. 1. Extended holiday hours are 9 a.m. to 5 p.m. Dec. 26-31. The exhibit TapeScape, a massive indoor landscape made of 360 rolls (that's 22 miles) of packing tape, continues through Jan. 19. “Tough Art” continues through Dec. 31. Regular hours are 10 a.m. to 5 p.m. daily. Admission is $13 for adults, and $12 for children ages 2 to 18 and senior citizens. Call 412-322-5058 or visit www.pittsburghkids.org.Carnegie Museum of Natural History, 4400 Forbes Ave., Oakland, is displaying its decorated holiday trees, six fresh 20-foot Colorado spruce trees with the theme “Embracing the Art of Play,” through Jan. 12. The Neapolitan presepio Italian Nativity scene is on view through Jan. 9. Museum hours are 10 a.m. to 5 p.m. Tuesdays to Saturdays, with extended hours until 8 p.m. Thursdays, and noon to 5 p.m. Sundays. Admission is $17.95 for adults, $14.95 for senior citizens, and $11.95 for students and children ages 3 to 18. Admission after 4 p.m. on Thursdays is discounted. Call 412-622-3131 or visit www.carnegiemnh.org.Heinz History Center, 1212 Smallman St., hosts “Poptastic!” focusing on Pittsburgh artist Burton Morris and more than 100 original works of art through Feb. 23. The exhibit “Pennsylvania's Civil War” continues through Jan. 5. History Center admission is $15 for adults, $13 for senior citizens, and $6 for students and children ages 6 to 17. Call 412-454-6000 or visit www.heinzhistorycenter.org.