In other fields, salaries rise to attract sufficient applicants. In teaching we have too often simply lowered our standards. Now turn to some cures which we will call catching, keeping, and converting. If keeping were spelled with a 'c' my points would be even easier to remember. The most efficient recruiting engine we will ever have is the cadre of enthusiastic, well-prepared high school science teachers.
Counter examples abound.
I was there. Teachers must be assigned to teach only courses for which they have sufficient preparation. Science teachers must have real opportunities for professional development and scientific education. We will likely recruit more science teachers by collaboration with the colleges of education than any other way. Collaboration between colleges of education, science departments, and state certification officials can create paths into the profession after a time in other parts of the work force.