Butler County Heritage Center, 119 W. New Castle St., celebrating the 150th anniversary of the birth of the oil industry with new exhibits, will be open Wednesdays and Fridays from noon until 4 p.m. during May. Admission is $5 for adults, $2 for children ages 5 to 17, and free for those 5 and younger. The Heritage Center is owned and operated by the Butler County Historical Society. Call 724-283-8116.

Lowrie/Shaw House, built in 1828 by Butler's only United States senator, will be open during May on Wednesdays and Fridays from noon until 4 p.m., with the last tour beginning at 3 p.m. Admission is $3 for adults, $1 for children ages 5 to 17, and free for those 5 and younger. The house museum is located at 123 West Diamond Street, directly behind the Butler County Courthouse. Call 724-283-8116 or visit the Web site, www.butlerhistory.com.

Harmony Museum on Mercer Street in Harmony, offers regular guided tours from 1 to 4 p.m. daily except Mondays and holidays; reservations are suggested for weekends and required for groups. Call 724-452-7341 or 888-821-4822, or visit the Web site, www.harmonymuseum.org.

<B>National Aviary</B>, 700 Arch St., offers free admission to mothers and grandmothers on Sunday for Mother's Day. Regular admission is $10 for adults; $9 for senior citizens; $8.50 for children ages 2 to 12; and free for children younger than 2. Regular hours are 10 a.m. to 5 p.m. daily except Christmas Day. Free admission is offered on Mother's Day for mothers and grandmothers. Call 412-323-7235 or visit the Web site, www.aviary.org.<B>Pittsburgh Children's Museum</B>, 10 Children's Way, Allegheny Square, will host "POPS: We Were Family" about former Pirates player Willie Stargell at 1:30 and 2:30 p.m. Saturday. Mother's Day Jazz is planned for 2 to 3:30 p.m. Sunday. The traveling exhibit, "Exploring Trees Inside and Out" continues through May 17. Regular museum hours are 10 a.m. to 5 p.m. Mondays to Saturdays; and noon to 5 p.m. Sundays. Admission is $9 for children 2 to 18 and senior citizens and $10 for adults; children younger than 2 are admitted free. Call 412-322-5058 or visit the Web site, www.pittsburghkids.org.<B>Carnegie Museum of Natural History</B>, 4400 Forbes Ave. in Oakland, hosts "Dinosaurs in Their Time." Hours are 10 a.m. to 5 p.m. Tuesdays through Saturdays, with additional hours until 8 p.m. Thursdays, and noon to 5 p.m. Sundays. Closed major holidays. Regular admission, which includes the Carnegie Museum of Art, is $15 for adults, $12 for senior citizens, and $11 for students and children age 3 and older, and free for members and children younger than 3. Call 412-622-3131 or visit the Web site, www.carnegiemnh.org.