They are three little letters that could imply a four-letter word you probably don't want your kids saying, much less wearing.
A Valley school is taking some heat for T-shirts which some say have a questionable message.
At first glance, the W, T and F really grab your attention.
"Everyone knows what it means," said concerned mother Tara Lopez.
But underneath in smaller print, it reads, "We're the Falcons."
"This is not bad, this is good," North Pointe High senior Cameron Pinches said.
"We're not going around saying 'WTF' like it's a bad thing," said fellow classmate Phil Briggs.
But Lopez didn't see it as a good thing. Her daughter goes to the charter school for grades seven through 12.
"My daughter came home from school two days ago and she told me that she wanted a spirit shirt and that the principal decided to put 'WTF' on the shirt," Lopez said.
"We're being who we are and, yeah, it's supposed to be a little bit outrageous because that's just a part of who we are," said student Nicole Marsh.
Lopez said she called the school and was told the principal came up with the idea.
"When you look at the dress code it says 'respect,' that's number one. I don't think that's showing respect at all. He needs to follow the dress code if the kids need to follow the dress code," said Lopez.
She said her daughter got in trouble a few days ago for wearing a flower headband because it went against dress code.
"I thought, 'Wow that's a double standard.' You can't wear a flower, but you can wear 'WTF' on your shirt?" she said.
The back of the shirt says "deal with it".
"You can take something that can initially be seen as a negative and turn it into a positive and that's what our main goal with this is," Pinches said.
But Lopez said she worries younger kids, like her daughter, will get the wrong message from wearing the shirts.
"Some of the kids are in seventh grade, so they're 12 years old and if their principal tells them that's cool and they see kids having fun, it's spirit week, then it's considered acceptable to talk that way. I don't want my daughter talking like that, especially at school," she said.
CBS 5 News reached out to the school and the district for a response to the shirts, but they didn't reply.
Copyright 2013 CBS 5 (KPHO Broadcasting Corporation). All rights reserved.