The sweat shirts zip up through the hood to completely cover the face, becoming a mask and making it virtually impossible to tell who is underneath.
They look more like Halloween costumes than casual clothing. Some have prints resembling Mexican wrestling masks or a member of the band Kiss; others look like gas masks, alien heads or skulls.
They're fashion statements to some, but to administrators in Orange County's Capistrano Unified School District, there's danger lurking under the hood. All six high schools last week banned hoodies from campus.
School officials sent e-mails to parents telling them to shop for Christmas presents accordingly. "Before you complete your gift buying for the holiday season, we want to let you know that any sweatshirt that zips up all the way through the hood (mask or not) will not be allowed at school," the e-mail says.
School administrators say the problem is that someone could hide behind the mask. "There is no way to identify who kids are," said Tom Ressler, principal at Capistrano Valley High. "Generally, we don't think that is a good thing. It gives kids the opportunity to do something bad."
If hoodies were allowed, it would make it easier for strangers to sneak onto campus, Ressler said. And even if students wore the sweat shirts with the hood down, they could obscure their faces within seconds.
Teachers and administrators had seen only a few students with the hoodies, and none wore it with the mask pulled on, Ressler said, but officials at Capistrano Valley decided a week ago to ban them before they became a trend. The district's other schools followed soon after.
Other school officials in Orange and Los Angeles counties said they did not have policies specifically banning the "mask" hoodies.
Capistrano Valley's dress code says students cannot wear clothes that obscure their faces. Hats are not allowed, and students wearing regular hooded sweat shirts, which are still acceptable, must keep their heads bare.
Regular hoodies are worn all over campus, but students say the masked ones, sometimes called "burkas for boys," are the latest craze.
Sergio Magana, 17, a Capistrano Valley senior, bought two masked hoodies after he saw some of his favorite hip-hop artists, including Kanye West and Lupe Fiasco, sporting them.
"They bring the style and we roll with it," Magana said.
One friend owns the same-style hoodie West wore, with a skeleton on the sweat shirt and a skull on the hood, he said.
One of Magana's hoodies transforms him into Benjamin Franklin covered by a bandanna. Magana sees through two holes cut from Franklin's eyes. He bought it for $70 at a local skateboarding store. "It gets hot in there," he said. "But other than that, it's comfortable."
Magana said he wished the hoodies were allowed at school. "It's not gang-related," he said, "and we wouldn't wear them zipped up."
Others feel the hoodies are a fashion faux pas. "From a girl's point of view, they're ugly," said Lisa Harlow, 16, a sophomore. "Nobody wants to see a skeleton running around."
The hoodies are an unusual addition to Capistrano Unified's high school dress code, which mostly restricts scanty clothing, such as midriff-baring shirts and exposed underwear. It's one of the first pieces of clothing school officials felt the need to warn parents about buying, Ressler said.
"Maybe if you lived in Detroit, maybe you would need it to protect yourself from the cold," Ressler said, "but last time I checked, that's not an issue in California."