How much is a train ticket from Shanghai to Beijing??

There are three types of train operating between the two places.
The D-trains cost about 309 to 408RMB for the second class seat, 648RMB for the first class seat.
The G-trains cost about 553RMB for the second class seat, 933RMB for the first class seat.
For the common trains, it is suggested to search on the Train section on this website.