Locked door in magic school

Hi
I would like to know how to open the locked door in the magic school ?
What is behind that door ?
Do we really have to try and open it ?
Thanks in advance for the help and answers !
Jolinuk

I would like to know how to open the locked door in the magic school ?
What is behind that door ?
Do we really have to try and open it ?
Thanks in advance for the help and answers !

Jolinuk