Alpamare
Gwattstrasse 12
across the Seedamm the Alpamare is located - a large water entertainment park for the whole family.
Watch a game of the ice hockey team
Walk across the Seedamm to the other side of lake to Pfäffikon
Voralpen-Express
Take the train Voralpen-Express (http://www.voralpen-express.ch) from Rapperswil to Arth-Goldau if you like very scenic train rides
Zoo
Knie's Kinderzoo Circus Knie's Children's Zoo is not only for children and very the center of town walking distance with kids from the center. Open from March to October.