My sister and I went to the zoo and conservatory (http://www.comozooconservatory.org/) last Thursday (her birthday). The pic above is a of a baby "mustache monkey" (I could look up the actual name but I don't feel like it). They also had a baby orangutan and a baby giraffe - both adorable, of course.
It was a beautiful day outside but the conservatory is nice to visit even (or especially) on a crummy day. They still had there spring flower display in the sunken garden, showing tons of tulips, daffodils, foxglove, and lilies. I believe that the summer show will begin in early May.
One of the nice things about the zoo and conservatory is that they don't charge a hefty fee. I think that the suggested donation is two dollars, which means that it is an affordable outing for families, students, and even poor artists :)