National treasures

One of the oldest collections of Americana in the country is in our own town of Concord. At tomorrow’s Free Evening at the Concord Museum, you can see the contents of Henry David Thoreau’s house at Walden Pond and the exhibit “Setting the President’s Table’’ featuring more than 100 pieces of porcelain used by American presidents. Kids can design a powder horn and go on museum hunts. Aug. 19 from 5 to 8 p.m. Free. Concord Museum, intersection of Lexington Road and Cambridge Turnpike, Concord. 978-369-9609. www.concordmuseum.org