Day trip to amsterdam

There is probably a hop-on/hop-off boat. We used one a few years ago and it stops in some convenient places.

LOVE Amsterdam…….walk along the canals, eat a stroopwafel, find a lovely place to enjoy a meal while watching the canal boats glide by…..we LOVED the Rijksmuseum but you may not have time to do that……go to Van Stepele and eat their incredible cookies made on the spot that will melt in your mouth!

Is there any way you could at least spend the night in Amsterdam? A day trip would mean at least 7 hours on the train and make for a very short visit. Depending on the time of year you might also have limited daylight. If you're set on only a day trip, if there are any specific museums you want to see (Anne Frank House, Van Gogh, Rijksmuseum) be sure to buy advance tickets and be aware of the timeframes to secure tickets for specific dates.

The Hop on/Hop off buss exists for to relieve tourists who cannot conceive of any other way to see a city of some of their money.

You do not need it. The best way to explore Amsterdam is on foot. Everything of interest is within walking distance of the main station, where you will arrive.
Doing a canal tour however does offer a nice introduction to the city.

Any suggestions?

Don't make it a day trip.

I love Amsterdam (and Paris) and can't conceive of leaving Paris to simply do a "drive by" of Amsterdam. Even an overnight just seems like a lot of effort (to/from on the train) for not enough pay-off. I'd say focusing more on Paris (and environs) is better than tacking on Amsterdam.

My other suggestion is to book a week in Amsterdam for the Spring next year :-)

Too far to do as a day trip. Waste of time to come out of Paris only to have a few hours in Amsterdam, a tiring day of travelling and not insignificant cost in train tickets. In my opinion anyway.