The extra configurations may be to let your laptop auto connect
to the school's wireless system, adding a shortcut which can access
certain locations on the school's server, configuration to connect
to the school's wireless printer, installing softwares which the
teacher can monitor your screen during a test which u can access
the internet.
All these programs will slow down your computer's performance.
Remember to back up important school work data.
I used to work in my school's IT support department, my job is
to help others configure all these and "reformat" their system
drive if their is too much problem. Quit working after a few
months, pay too low 