Several of my colleagues from ourAround the Mall blog, got a sneak preview of the new Spark!Lab at the National Museum of American History, which reopens on Friday after extensive renovations. The ATM folks received a lesson about carbon dioxide. They watched dry ice sublimate and learned how excess CO2 is causing acid rain that is slowly dissolving the marble on Washington D.C.'s monuments and buildings. Beth, head blogger over at ATM, promises “a festival of test tubes and cannon balls, slabs of wax and strings, kites and keys, and machines that whir and liquids that bubble and smoke” at the new activity center. Though it may be aimed at younger students of science, this still sounds like fun even for those of us many years from being kids.