Many families with young children are put off by the red-light-district, coffee-house, stag-party reputation of Amsterdam. However, it is a great city for young children.
NEMO is a children's science museum in the main harbour, right next to Central railway station. It has to be the best kids musem in Europe. Every exhibit is interactive, kids can dress up as scientists and blow things up in the lab (carefully helped by real scientists!). They can also appear on TV, wrap themselves up in giant bubbles and watch a fantastic great-egg-race-style show every half hour.
Despite being in Holland, every exhibit is also described in English and the presentations and announcements are also bilingual. The museum is great for kids aged from 4 to 14, and is so big that you can easily spend several hours there.
Once you have exhausted yourselves there, try the Pannenkoekenhuis, a pancake house in a 17th-century warehouse overlooking the canal on Prinsengracht. The kids' pancakes come with toys, games and fireworks to finish the day off with a bang!
Is this your business?