I think the Parc Monceau, 5 boulevard Courcelles 75008 is one of the most elegant parks in Paris. Constructed in the late 1800s, its beauty has inspired many from Marcel Proust who took daily walks in the park to Claude Monet who painted several landscapes of it. The park includes a gorgeous pond and an amusing collection of petite architectural features such as an Egyptian pyramid.
The twenty acre park has grassy spaces for picnics, play equipment for kids and paths that are used for both walking and jogging. It is definitely a park that both adults and kids will enjoy. And after your visit to the park, don't forget to check out the fabulous Musée Nissim de Camondo that lies adjacent to the park.