Piaget’s stages also provide guidance about strategies that are likely to be effective in teaching children at different age levels. For instance, given the abstract nature of historical time, elementary school teachers planning history lessons should probably minimize the extent to which they talk about specific dates before the recent past (Barton & Levstik, 1996). Also, especially in the elementary grades-and to a lesser degree in middle and high school-instructors should find ways to make abstract ideas more concrete for students.