Pupils at Millais School in Horsham have yet to return to their normal timetable after a fire swept through the building on Thursday (March 30).
Individual year groups have been asked to come in for hour-long slots for an update today (March 24).
On Saturday (March 22) David Brewer, director of business services, said work has begun to restore school services including telephones.
“If you have any need to contact the school for essential information, please use our central email address at firstname.lastname@example.org.
“Arrangements for Monday are set out in a separate letter under the parents’ secure login section of this website and the information has also been sent direct by email.
“Thank you for your patience and understanding.”
Sussex Police said the incident is being treated as a crime.