Shedd aquarium, a not-for-profit, tax-exempt organization, gratefully acknowledges the sustaining contributions of the people of chicago, state of illinois and chicago park district. shedd is an accredited member of the association of zoos and aquariums, a smithsonian affiliate, and humane conservation certified by american humane.. Looking for fun things to do for free? now's the time to visit the shedd aquarium. on mondays and tuesdays from now through november, general admission is free.. Chicago the shedd aquarium is offering free admission to illinois residents for the rest of september. shedd is also offering free days on oct. 3 and 10. free admission includes all permanent.