Central Station is only 15 minutes by train. From here about 8 trains per hour are going back to Schiphol (AMS).
From Central Station you walk towards Damsquare and look around. If you think it's interesting you can walk back via the red light district or you can take a boattrip of 1.5 hours which shows you a bit more of Amsterdam.
If you like to see windmills, you can travel a lit bit further (another 15 minutes) to the Zaanse Schans. About 12 mills are standing along the river and all kind of 'typical'Dutch things are here freely to explore (wooden shoe factory, cheese making, etc)
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Best regards
Nochurch
PS Have you already played
Virtual Xplorer?