MALENY High students Beth Goodrich and Rosie Bright will be chopping their locks for charity as part of the World's Greatest Shave for a Cure.
Rosie said the pair had been thinking about shaving their heads for more than a year.
"We both talked about doing it last year but we never had the guts to do it," she said.
"We just thought we are in our last year of high school, let's do something different and scary."
For Beth, it was about doing her bit to help others.
"It's exciting and we are helping so many people at the same time," she said.
"And it was not as scary because we decided to do it together."
The girls are the only two female students involved in the shave.
"There are two female teachers doing it and a heap of guys as well," Rosie said.
The 16 year-olds, from Maleny and Beerwah, want to raise $5000 for the Leukaemia Foundation.
"We have raised $1500 so far in one month and want to get to $5000," Beth said.
"Our original goal was only $1000 but we smashed that in a few weeks so we bumped it up.
"I'm getting really excited and a bit impatient.
"I just want to do it already," she said.
The girls will join principal Mr King, who will shave his head for $1000, Ms Tickle, the school librarian, who will shave her hair for $2000, chaplain Chris Davis, who will be shaving his beloved beard for $5000, and sports teacher Ms Hyde who will chop her luscious locks for $10,000.
Money raised from the World's Greatest Shave is spent on research and on providing free home-away-from-home accommodation for the families of those affected, as well as free transport to and from treatment.
To support Rosie, Beth and Maleny State High School donate online, website