The command xrandr can be used to change the screen resolution from the command line. Execute the xrandr command to see available screen resolutions. The output will look like this:

Screen 0: minimum 320 x 240, current 1440 x 900, maximum 1440 x 900
default connected 1440x900+0+0 0mm x 0mm
   1440x900       50.0*
   1360x768       51.0     52.0
   1152x864       53.0
   1024x768       54.0
   960x600        55.0
   960x540        56.0
   840x525        57.0     58.0
   800x600        59.0     60.0
   800x512        61.0
   720x450        62.0
   700x525        63.0
   680x384        64.0     65.0
   640x512        66.0
   640x480        67.0     68.0
   576x432        69.0
   512x384        70.0
   400x300        71.0
   320x240        72.0

To change the resolution:
xrandr -s 1024x768