In mid June, my daughter and I will be spending 9 nights in Europe -- 4 in Paris, 3 in Amsterdam and 2 in Prague. We are starting out in London, where she was on a study abroad program. I am meeting her there, and we plan to chunnel to Paris, train from Paris to Amsterdam, and then an overnight train to Prague (Amsterdam to Cologne, and then getting the overnight there). Would you recommend a train pass for this trip, or just location to location?
Definitely go with point to point tickets.
No to rail pass. Just get ordinary advance purchase tickets.
You only have 3 rail trips. A rail pass is not valid on the Eurostar (London to Paris). You can get cheap advance purchase tickets for all 3 trips.
For Eurostar (it is not called "chunnel"), go to: http://www.eurostar.com/
For Paris to Amsterdam, the company is "Thalys": https://www.thalys.com/
For Amsterdam - Cologne (aka Köln) - Prague, go to the German Railways site: www.bahn.de
For all train other information, read the excellent "Man in seat 61" website: http://seat61.com/
The Thalys required Eurail reservations are often as much as advance purchase nonrefundable tickets.
For night trains, the biggest cost is the sleeping compartment or couchette, which is not covered by the Eurail pass.
Dump the Eurail Pass idea - it's a waste of money in almost EVERY situation.
The overnight train from Köln (Koeln) to Prague also stops in Duisburg, which is closer to Amsterdam than is Köln. Unless you have some burning desire to see the Köln train station, take the IC from Amsterdam to Duisburg and board the night train there. Either way, only the night train would be covered by a single day of a rail pass (7 PM rule). The trip from Amsterdam to Köln or to Duisburg would be a separate day of your pass (or a ticket), so you have four days for your three trips (really three days for 2 trips since the Eurostar is not covered).
I don't think you can get 4 country passes for only three days.