Departures leave a void at the head of the class.

Byline: Melodee Hall Blobaum

Aug. 14--Karen Nixon has been in and out of her Blue Valley High School classroom all summer, getting ready for the academic year that starts Thursday.

But those preparations have been bittersweet.

"Everything I'm doing now, I'm doing for the last time," said Nixon, a math teacher who expects to retire next spring after 32 years in the classroom.

At 52, Nixon is among thousands of teachers in Missouri and Kansas who are starting the countdown to retirement.

Those departures, combined with an exodus of teachers before their fifth anniversaries in the profession, are having a profound effect on schools and children:

--Schools are losing their most experienced teachers just as they face increased pressure to improve test scores.

--Already confronting shortages in math, science, foreign language and special-education teachers, schools could find these spots even tougher to fill.

--Families saying farewell to much-loved teachers could see less-experienced replacements.

"Not a lot of people are going into the teaching field right now, and we don't have the people going into the fields we need," said Martha Gage, director of teacher education and licensing for the Kansas Department of Education.

The number of retirements has increased in both states and is expected to rise even more.

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