Each year since 2009, visitors to the World Science Festival's Street Fair in New York City have experienced the Math Midway, a large and crowded carnival filled with mathematical toys and activities such as square-wheeled bicycles you can ride on a cycloidal track and plastic polyhedral solids that reveal surprising cross sections when you shine laser light through them. The Math Midway is one of many successful components unique to the World Science Festival, which the Sloan Foundation helped launch though its program on the Public Understanding of Science and Technology. Most science festivals struggle to present any kind of compelling mathematical content at all. The creators of Math Midway would now like to share what they have built, as well as what they have learned, with science festival planners and participants throughout the country. Funds from this grant will support efforts by Museum of Mathematics founder Glen Whitney to develop up to 20 portable versions of the Math Midway exhibitions that can travel to science and mathematics festivals across the country. The Science Festival Alliance, a Sloan Foundation grantee, has already arranged for these exhibits to be displayed and tested by organizations operating under its umbrella, including science festivals in San Diego, Philadelphia, Harlem, Cambridge, and the Bay Area. The project will also train local mathematicians to staff these exhibitions. Independent evaluation of the construction, deployment, and reception of the first six such kits is also part of the project plan under this grant, and will help clarify what works and what next steps might make sense going forward to enhance public engagement with mathematics.