Sus consejos:If you go with children, don't lost the zoo, El Tigre, 2 decks bus tour, Caminito and a good Tango show. Argentinian Peso has an excelent rate.
I went there with my wife and son, excelent prices, food, parks, zoo, museums, Casa Rosada, Caminito, Puerto Madero, Señor Tango, Tigre...