Not a big fan of zoos and animals behind cages, but if you can spot Flamingos in the east-centre of Amsterdam, then count me in <3 ! You can actually see them while riding the bike on Plantage Middenlaan, quite a beautiful scene.
Note: De Plantage next to zoo is quite cool cafe/restaurant, with a mix of vintage style and industrial elements of the old buildings of Artis. Great atmosphere, and ideal for a more sophisticated outing.
Hannekes Boom is one of the nicest waterfront café in Amsterdam to have a beer when it's sunny. Close to Central Station, the place isn't crowded by tourists, but you need to be there early to get a seat.