The mid-term exam can be found here (pdf) and here (tex) after 10 o'clock Monday 27th of March. The deadline is Friday 31st of March (see files for details).
You can now find a draft of the solution manual to the mid-term exam here.
Some time early May we will start putting old exam sets here for you to have fun with. (You can make paper airplanes for example.) Eventually solutions will appear as well.