Butler County Heritage Center, 119 W. New Castle St., will display two model railroads Sunday afternoons through Jan. 4. Hours will be noon until 4 p.m. In addition to a small, new train display, the Heritage Center is also home to the Jay Bee Miniature Circus, Austin and Bantam cars as well as the "jeep," which was produced in Butler, and exhibits on Pullman-Standard, the steel, oil and glass industries. Museum admission is $5 for adults, $2 for children ages 5 to 17, and free for those younger than 5. Call 724-283-8116.

Lowrie/Shaw House, built in 1828 by Butler's only United States senator, is open through the end of the year on Mondays, Wednesdays and Fridays (except closed Dec. 24). Hours are noon until 4 p.m., with the last tour beginning at 3 p.m. Admission fees are $3 for adults, $1 for ages 5 to 17, and free for ages 5 and under. The house museum is located at 123 W. Diamond Street, directly behind the Butler County Courthouse. Call 724-283-8116 or visit the Web site, www.butlerhistory.com.

<B>National Aviary</B>, 700 Arch St., will offer one free child admission with the purchase of an adult admission each Sunday in December. Hours at the aviary will include being closed Dec. 25, and open 10 a.m. to 3 p.m. Dec. 31 and 10 a.m. to 5 p.m. Jan. 1. Regular hours are 10 a.m. to 5 p.m. daily except Christmas Day. Regular admission is $9 for adults; $8 for senior citizens; $7.50 for children ages 2 to 12; and free for children younger than 2. Call 412-323-7235 or visit the Web site, www.aviary.org.<B>Carnegie Museum of Natural History</B>, 4400 Forbes Ave. in Oakland, is exhibiting "Born of Fire: The Life and Pottery of Margaret Tafoya" through Jan. 4. "Dinosaurs in Their Time" continues. 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. 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 www.carnegiemnh.org.<B>Phipps Conservatory and Botanical Gardens</B> in Schenley Park is displaying among the plants some Donald M. Robinson photographs of the Chihuly glass that was exhibited at Phipps last year. The photography will be shown through Jan. 22. Phipps is open daily from 9:30 a.m. to 5 p.m. and until 10 p.m. on Fridays. Admission rates are $10 for adults, $9 for seniors age 62 and older and students with ID, and $7 for children ages 2 to 18. Phipps members and children under 2 are admitted free. Call 412-622-6914 or visit www.phipps.conservatory.org.<B>Carnegie Science Center</B>, One Allegheny Ave. next to Heinz Field is offering holiday features such as "The Polar Express: The IMAX® Experience" in the Rangos Omnimax Theater through Dec. 31, and a holiday magic laser show for all ages presented daily at 3 p.m. in the Buhl Digital Dome high-definition planetarium. The traditional MessFest is again planned for Jan. 1 with the messiest, most disgusting science demonstrations and activities. Regular hours are 10 a.m. to 7 p.m. Fridays and Saturdays and from 10 a.m. to 5 p.m. Sundays through Thursdays; closed holidays. The center will be closed Dec. 28 because of the Pittsburgh Steelers game next door. Regular admission is $14 for adults and $10 for senior citizens age 62 and older and children 3 to 18. Parking is $3. Call 412-237-3400 or visit the Web site, www.carnegiesciencecenter.org.<B>Heinz History Center,</B> 1212 Smallman St., features its new exhibit, "Pittsburgh: A Tradition of Innovation," tracing Western Pennsylvania's imprint on the United States and the world. From the Meadowcroft Rockshelter in Avella,16,000 years ago to the roads, planes and houses of today, the long-term exhibition features people's stories. Hours are 10 a.m. to 5 p.m. daily, except holidays. Admission is $9 for adults, $7 for senior citizens older than 61, $5 for students with ID and for children ages 6 to 18, and free for children younger than 6. Call 412-454-6000.