My flight out of Italy stops at CDG at 10 PM on a Wednesday night in August. The connecting flight does not leave until 1 PM the following afternoon (I know it's not great, this was not my first choice).

I have never been to Paris before and neither has my cousin. Would it be reasonable to take the RER or taxi into Paris to walk around in the morning and then go back around 10 AM so we are at the airport in time for our flight back to the states? I know this might be tough but I am in my 20's (have been to Europe a number of times) and would not mind not sleeping that night if it meant I get to see a little bit of Paris. Is this doable at all? Any suggestions would be great. Thanks!

I think given your age and travel experience you would be able to do it. I think it would be best to just hop a cab as soon as you arrive and get a hotel somewhere along the RER B in central Paris. That would probably get you into Paris about 11:30 or so since your flight is only from Italy. Then you could either take the metro back out to CDG in the morning around 9:30 once the morning rush dies down or order a cab. Since you would arrive late-I would stay somewhere with something going on though-like the Marais or the Latin Quarter or Montparnasse to at least make the most of the time you will have.

agree..take the RER into Paris; stay in the Marais or Latin Quarter and enjoy a little bit of the city. see the link below to see the train map

http://parisbytrain.com/

If you need a couple of inexpensive hotel suggestions-here are 2 I know that are good and good bargains. Neither is right on the RER B line but both are central and easy by cab. Both sould have a room for 2 under 90 euros, which is good for central Paris:

Hôtel du Sejour Beaubourg (good deal near the West side of the Marais)

http://www.hoteldusejour.com/

Hotel Odessa in Montparnasse:

www.hotelodessaparis.com

There are probably lots of others from other folks but both of these are in lovely areas and should fit a student budget without being a hostel.

Our daughters recently had a similar long layover. Overseas flight arrived at 8:00 AM and connecting flight wasn't until 6:30 PM. They opted to take the Air France bus (around 14 euros I think) to save a little time and hassle rather than the RER. They spent several hours enjoying Paris and returned to CDG about 2-1/2 hours before their Athens flight.