Is the Thalys train the way to go? or are there other options? I dont think I saw cheap flights. the 1 way train costs 222 Euros for 3 of us.
I'm not sure where you're getting your fares from, but by booking in advance (up to 90 days in advance) you can get discount "smoove" fares for as low as 35 euro per person....105 Euro for the 3 of you. Go to thalys.com, and down at the bottom under Netherlands, select "English." You can book a paper ticket that will be a pdf file that you can store on your computer and print out before you leave.
[Edit] You won't find any cheap airline flights on that route....the fast trains have made them virtually obsolete.
If you can get a Smoove fare, Thalys is your best combination of speed and price.
If price is more important than speed, then take a Eurolines coach (highway bus). Booked well in advance, you can get a super promo fare as low as €17.
Walking or stealing a bicycle is probably the cheapest...
Or like the other folks said, you can catch a pretty good Thalys deal if keep an eye out on the sales.
Unfortunately a Eurolines coach from Amsterdam to Paris has crashed on Friday in northern France causing a fatality and injuries. BBC news state that the investigation is questioning if the driver fell asleep.
Every year there are a number of crashes involving coaches. Every time an investigation is started, and avery time there is a cry for further investigation into pressure on coach drivers.
Taking into account the amount of coaches driving around, it is still a pretty save way to travel. I hope this time something will be done to lift the pressure to ensure even safer travel.
I would however consider travelling by (hi speed) train. Much faster and more relaxed/comfortable.
i don't know if it is the cheapest--i imagine a bus would be cheaper--but i can tell you that it IS quick, easy and comfortable. from the door of our hotel in amsterdam to the door of our apartment in paris was less than four hours--and that's counting walking to the train station, boarding the train, train travel time, transferring to the metro, a metro transfer, and the walk to the paris apartment. to fly, you'd spend half of that time in line for security; on a bus, well, i imagine it is a longer ride. 222 E for three people is still right under $100 USD per person--i'd say that's pretty cheap. though do try to get the 35 E fare. and have a great trip. we loved amsterdam.