Vandals left their mark on Patuxent Valley Middle School during the holiday weekend, covering the building with blue and yellow spray paint.
The graffiti -- including obscene remarks, references to marijuana and racial slurs -- was discovered at the Jessup school about 3:30 p.m. Christmas Eve, police said.
More than two dozen markings were found on some windows and most of the exterior brick walls.
The vandals included a holiday message in their graffiti, writing: "Deck the school with lots of spray paint, fa la la la la la la."
One wall of Bollman Bridge Elementary School, which is next to Patuxent Valley Middle, also was vandalized.
No arrests have been made in the incident, police said.
School officials could not be reached for comment yesterday.
In the 1994-1995 school year, it cost the school system more than $400 to remove graffiti from Patuxent Valley Middle School.
Guilford: 7200 block of Oakland Mills Road: A black, two-door 1994 Toyota Paseo with Maryland tags CLA-493 was stolen Saturday between midnight and 10:15 a.m.