Imagine a world without science and math teachers.

For some kids, that might be the definition of paradise.

But for anyone concerned about U.S. competitiveness in technology, engineering, medicine and other mathematics- and science-based fields, that's a scary scenario.

A National Academy of Sciences study in 2005 documented that U.S. 12th-graders performed below average among 21 countries, when tested on their science and mathematics knowledge.

Study authors also found that in 2004, China produced 500,000 engineering graduates, India produced 200,000 -- and the U.S. had 70,000.

And an industry-sponsored poll of students several years ago concluded that, "Most students have no idea how to define engineering. When asked what they think engineers do, students' responses ranged from 'drives a train' to 'operates machinery.' Only four percent of students say that engineering requires math skills."

Without kids interested in math and science, you don't get math and science teachers. Conversely, without math and science teachers who are good at their jobs, you don't get kids interested in math and science.

Add to that a marketplace that pays higher wages for private sector science- and math-related jobs than to teachers of those subjects, and you've got a crisis brewing.

All this is not news. As the number of math and science teachers nationwide diminishes, efforts have been under way across the country and in Maine to encourage college students to pursue careers teaching those subjects.

But as reporter Colin Hickey wrote this past weekend, despite a recent effort to spread scholarship money around to would-be science and math teachers in Maine -- and a subsequent rise in the number of teacher candidates -- the state is still in the throes of a teacher shortage in those two areas.

The state's economic growth is increasingly dependent on attracting new jobs that require technical and scientific skills. And while much of Maine's attention has been on attracting those jobs and providing skills training at the community college level, there's room for a lot more effort to promote math and science teaching as a career.

That work should include studying the possibility of alternative career paths to teaching science or math -- such as allowing professionals in those fields to do a limited amount of teacher training in order to work in a classroom -- as well as giving serious consideration to paying math and science teachers a higher wage, which is guaranteed to raise the hackles of teachers' unions.

It's going to take innovative steps to return this country to the dominance it once enjoyed in the fields of science and mathematics.

We can't do it without teachers.