Beautiful parks and gardens
Jardim da Estrela - this a big park in our neighborhood (Principe Real) that has playgrounds and a little cafe where we got some lunch. Most of the parks have kiosks where you can buy an espresso for about 50 cents.
As former preschool teachers, we found it very interesting to see how parents interact with their children here. In general, it seems people are not shy about telling other people's children to behave and there are even signs in some stores that basically remind parents what is expected of their children.