SANTA BARBARA, Calif. -

Monday's stabbings near Goleta, allegedly at the hands of Nicolas Holzer, came just weeks before the start to the new school year.

Friends and teachers of Sebastian and Vincent Holzer, the two brothers allegedly killed by their father, along with their grandparents, will have particularly heavy hearts as they see the boys' empty desks.

The principals at their two schools reacted Wednesday to the tragic loss of the young lives.

An empty classroom at La Colina holds mementos of happier times -- photos that include a smiling, cherub-faced Sebastian Holzer.

The 13-year-old spent fourth period of his 7th grade in this room last year during AVID (Advancement Via Individual Determination), a college readiness course.

"What was so impressive about Sebastian, he was a very high achiever, very positive, friendly, outgoing, very much connected with all," said La Colina Junior High principal David Oritz.

A copy of Sebastian's class schedule reflected a heavy academic load that included pre-algebra, science and Spanish, in which Ortiz said the teen had a deep interest.

"As I talk to my colleagues there is outrage because Sebastian and his little brother .. they had friends through activities so it's all over the community," said Oritz.

And that community extends down the road to Foothill Elementary school.

Sebastian's little brother Vincent would have been a 4th grader there this year.

Teachers and school employees are mourning the loss of the 10-year-old who loved to help others.

"The teachers speak very highly of him," said Briget Braney, Foothill's new school principal. "He was a sweet boy. So nice and the secretary said he was a social studies buff and came in early in the morning to help open doors for the day custodian. He was a presence on the campus," said Braney.

Principals at both campuses are bringing in grief counselors and will plan a memorial celebration once school starts, to honor the two young brothers taken far too soon.