Visitors will have to sign in when classes resume Thursday.
About 100 students, parents and teachers gathered in the school gym Sunday to learn how the administration is responding to the death of John Klang on Friday.
The school superintendent says the most important tasks ahead will be securing the school and getting back into a routine. He says the armed officer will guard the school indefinitely.
The student accused of opening fire on the principal has a court appearance on Monday.
AP
