The negotiating body for Scottish teachers last year granted them the right to take career breaks of up to five years, with the guarantee of a job at the end - but very few appear to be aware of the option.
Scotland's largest teaching union, the Educational Institute of Scotland, admitted this week there had been no nationwide publicity.
And a charity that specialises in placing volunteers abroad has taken matters into its own hands and produced publicity materials telling teachers: "Now when you volunteer, you're guaranteed to keep your job."
Scottish teachers have been entitled to take a career break since August 2008 when the Scottish Negotiating Committee for Teachers agreed the change to teachers' terms and conditions. Those granted breaks of two years or less are entitled to return to their old posts, while teachers taking a break between two and five years would return to employment in their authority but not necessarily to their previous post.
Drew Morrice, assistant secretary at the EIS, said: "There is no way of measuring what uptake is like. My impression is it has not been high."
Scotland officer for Voluntary Service Overseas, Susanne Darcy, said: "Teachers are not aware of this at all. There is a lot of work to do to make sure the message is out there."
Teachers who decide to spend their career break volunteering can even have their pension payments maintained, she added.
In March last year, the UK Government made pound;13 million available in pensions benefits to teachers and other public sector workers willing to volunteer abroad. Launching the three-year pilot, Ed Balls, England's Secretary of State for Children, Schools and Families, said: "Ensuring pension contributions are paid, at no cost to the school, authority or individual teacher, will encourage more sabbaticals and career development breaks."
VSO, however, is still struggling to fill posts for teachers abroad - 80 are lying vacant - and the charity is critical of the Scottish Government for failing to publicise career breaks, which it argued could also help combat the recruitment crisis.
Ms Darcy said: "If teachers volunteer, that would free up jobs for newly- qualified teachers and allow those teachers beginning to stagnate in their jobs to go away and come back refreshed. Our placements would also give them more managerial experience and make them better able to apply for the promoted posts we know are going to need filling over the next five years or so."
Although teachers with two years' continuous service are entitled to apply for a career break, VSO requires three years' experience in the classroom, given that volunteers are often asked to train other teachers or act as education managers.
According to the SNCT handbook, there are no prescribed activities a career break must involve, but it cites caring for children, voluntary work, travel or study as examples.
Local authorities, however, can refuse permission. The SNCT handbook states: "It is for the council to decide whether the exigencies of service provision allow for a career break to be granted."
Primary teacher Caroline Ssentamu was granted a career break by West Lothian Council before special leave without pay officially became part of teachers' conditions of service last year. From February 2007, she spent 18 months in Malawi.
"My official title was continuing professional development facilitator," she explains. "I was working with other teachers and primary education advisers to give them training on everything from delivering maths lessons to management skills."
Malawi is introducing a new curriculum, a process that was underway when Mrs Ssentamu was working there. "It's a massive change from chalk and talk to looking at more group work and involving the children as individuals. It was very challenging for a lot of the teachers".
Back in Scotland, Mrs Ssentamu is now a development officer with A Curriculum for Excellence in the cluster that includes her school, Winchburgh Primary in West Lothian.
"Most of the skills I cited on my application were gained in Malawi," she says.