My friend and I have a 6 hour layover coming up next month in Amsterdam. Any ideas of what to do for that amount of time? Restaurants near the Schipol Airport (AMS)?

Schipol is the model for top new terminals throughout the world, so you may want to view what is available there.

http://www.schiphol.nl/Travellers/AtSchiphol/Maps.htm

Or check the VVV (Dutch Tourist Office) in the arrivals area - they do do short-term escorted mini-bus tours - planes often IME land earlier than scheduled now (to have a better on-time performance I think) and they do do short few-hour brief looks and if this is your only chance to see one of the world's most beautiful cities go for it - if they can guarantee you'll be back in plenty of time.

Schiphol Airport is only about 8 miles or so from the center of Amsterdam I think.

That's enough time you could train into central Amsterdam, look around, head back.

Okay, thanks everyone. I would hate to miss this awesome city!

If you want to store carry-on luggage, there are lockers both inside the departure area, as well as when you stroll outside the customs/baggage-claim area.

If you are transferring from an International (non-Schengen) flight to an intra-European (Schengen) flight, you may as well take your bags past customs, as you will have to do a security screening to get to the intra-European (Schengen) area anyways, so you may as well do it just once before returning to the airport and heading to the B/C departure gate area.

If you are transferring from an International (non-Schengen) to another International (non-Schengen) flight, then you can just leave them in lockers in the non-Schengen D/E/F gates area.

Yes you could head in by yourself and see a tiny bit of Amsterdam around the train station but if those mini-bus tours of short duration are still offered I'd pay more and see more. And be guaranteed back at Schiphol at a certain time.