Katara Cultural Village which has an esplanade to walk on, quite nice on a cool evening out with restaurants there and exhibitions to look at. Museum of Islamic Art during daytime, Souq Waqif in evenings, Sealine Resort on weekdays (entrance charge is cheaper then) if you want some camel/horse rides on the beach. People also have evening picnics on the parks along the Corniche. All major shopping malls have a theme park with rides mainly for children & mini rollercoaster ride for adults.