Historic Building Tour: St. Thomas the Apostle Church. 1-3 p.m., St. Thomas the Apostle Church, 5472 S. Kimbark Ave., 773-324-2626, free. Visitors learn about the history, architecture, and interior art of this remarkable building from docents Thomas Staszak, Karen Feeney, and Dr. Sarah Bond. Tour begins at the church’s east door at 1 p.m. sharp.
Opera. “Madame Butterfly.” 7 p.m., International House, Assembly Hall, 1414 E. 59th St., 773-753-2274, $50 VIP admission, $30 general admission, $20 university students with ID, free for International House residents. Tickets available at the door beginning at 6 p.m. The American Chamber Opera Company presents.
Tot Lot. 9 a.m.-noon, Hyde Park Neighborhood Club, 5480 S. Kenwood Ave., email@example.com, classes are $9 drop-in, $45 for a 10-session pass or $65 for a monthly pass. This class is intended for children 0-4 and their caregivers or parents to get together on a regular basis to learn, play and benefit from one another’s company.