Don't depend upon teachers to teach. Many of them do not know how beyond uninspiring repetition.
Challenge your children with projects and extra reading. Put what they learn to application. Mathematics: have children make change as if a cashier, or plan a bridge using trigonometry.
Have them read more than merely their textbook, but more creative and fun books on the same subject. Have them read more in depth books that stretch their mind and question the authority of the "authority."
Let the children know that their wildest dreams can come true with the proper plan and commitment. A dream becomes impossible if it is never dreamed in the first place.