Peace Corps volunteer Ralph Bernstein, right, 84, poses with students at the secondary school where he will be teaching in the Tamale region of northern Ghana Monday, Oct. 13, 2008. As a new volunteer, Bernstein is trying to get used to the heat and humidity in the equatorial African nation of Ghana, the bone-jarring rides over unpaved roads and unsanitary conditions. The Dayton, Ohio man is the oldest current volunteer in the Peace Corps and part of a tidal wave of volunteers age 50 and older. (AP Photo/David Horton)

Liberia, founded by freed American slaves in the 19th century, has struggled to turn itself around since the brutal war ended in 2003 and President Ellen Johnson Sirleaf took office two years later. The return of the Peace Corps, which pulled out shortly after rebels invaded the country in late 1989, is a sign of confidence in Sirleaf, a Harvard-edcuated economist and Africa's first elected female head of state.

``Sirleaf has done a tremendous job of bringing this country back from chaos and we want to be part of moving her country forward as rapidly as possible,'' Peace Corps director Ronald A. Tschetter told The Associated Press in an interview from Washington, D.C. ``This is a huge step for us to go back.''

Liberia's back-to-back wars, which lasted from 1989 to 2003, sparked vicious factional fighting that killed an estimated 250,000 and displaced millions. Charles Taylor, who launched the 1989 invasion, is now jailed in The Hague facing war crimes charges.

Tschetter said Sirleaf had been calling for the Peace Corps to return and urged it to focus on what she saw as the most crucial need: education.

The 12 volunteers arrive Sunday and will be sworn in the following day. They come from a program called Peace Corps Response, which mobilizes former volunteers for short-term humanitarian assignments worldwide. Tschetter said he hopes their experience will enable them to ``hit the ground running'' and get the program moving faster.

Volunteers normally serve two-year stints, but the first group will stay eight or nine months _ about the same length as the school year _ as the program begins rebuilding. Their numbers are expected to double or triple by the end of 2009, and if all goes well, the program will reach 75 to 200 volunteers within a few years, Tschetter said.

The volunteers, aged 24 to 68, will be assigned to rural teacher training institutes where they will mentor administrators attempting to revitalize the country's teacher training infrastructure, the Peace Corps said in a statement. Others will work with local libraries, parent teacher associations, local high schools, and health training programs.

The statement quoted Sirleaf as saying ``such short-term projects aimed at raising the capacities and capabilities of Liberian teachers would have a profound impact upon civil society as a whole.''

Earlier Wednesday, Tschetter met with Sirleaf in Washington and said two officials with her - the Economics minister and Liberia's U.S. ambassador - had been taught by Peace Corps volunteers in the 1980s. ``Clearly the 4,400 who have served (before in Liberia) have made a tremendous impact,'' Tschetter said.

Late U.S. President John F. Kennedy founded the Peace Corps in 1961, challenging college students to serve their country in the cause of peace. Since then, the Peace Corps has sent more than 190,000 volunteers to 139 countries around the world to help people in developing nations and serve as goodwill ambassadors for America.

About 8,000 American volunteers are currently serving overseas.

Political spats or conflict have forced the suspension of several programs this year. After Bolivia's president expelled the U.S. ambassador for allegedly inciting opposition protests in September, the Peace Corps pulled out its 113 volunteers.

The Corps' program in Georgia was also suspended when Russian tanks and warplanes invaded in August. The Kenya program was suspended at the start of this year after disputed presidential elections sparked nationwide violence, but volunteers began returning in June, Tschetter said.