“Impulse,” an interactive work consisting of oversized seesaws of various sizes with lighting and sound by CS Design and Lateral Office, will be installed at Cowles Commons beginning on April 18 and be available to the public until May 19. Part playground apparatus, part interactive installation, the 15 seesaws of “Impulse” transform the space with the sound and light emitted when people play on them, according to a news release from the Greater Des Moines Partnership. The installation will coincide with upcoming downtown events, including the Downtown Des Moines Farmers Market, which starts May 4 and Civic Center engagements, including “MJ” playing April 30 through May 5. The activation is a joint endeavor between Des Moines Performing Arts and Operation Downtown, in partnership with the Partnership. “Impulse” is a production of Quartier des Spectacles Partnership and distributed by QDSinternational.