The emphasis should be on how well the K-12 students of these teachers are learning science and mathematics and on how the teachers' performance was affected by their postsecondary curricular experiences.
(The emphasis; should be; on how well the K-12 students of these teachers are learning science and mathematics and on how the teachers' performance was affected by their postsecondary curricular experiences) (the K-12 students of these teachers; are learning; science and mathematics) (the teachers' performance; was affected; by their postsecondary curricular experiences)
The emphasis the K-12 students of these teachers the teachers' performance
should be are learning was affected
on how well the K-12 students of these teachers are learning science and mathematics and on how the teachers' performance was affected by their postsecondary curricular experiences
science and mathematics
by their postsecondary curricular experiences