We have a A201 which has sat in a draw for a few years with a dead battery.  We want to see if it still works but cannot work out how to get the back off to check which battery is needed.  Can anyone help with how to remove the back.  Thanks.

I dont exactly remember how that Casio A201 looks like on the back, but if it has around 6 square holes on the backplate you need a special tool (google: watch case tool). I have done it with in the past with a small pair of pliers, but you dont want to loose grip and scratch the watch. (which does happen 80% of the time 😛)