The dividing line between high school and college has never been entirely clear, explains a historian of American education. In fact, for most of the 19th century, it was difficult to distinguish between high schools and colleges. It wasn't until the early 1900s that high school and university officials drew firm boundaries between the two institutions, and even then, it remained hard to distinguish between high school and college-level work. Moreover, there are some benefits to blurring the boundaries, the author argues, pointing to current efforts to promote dual enrollment, early colleges, and other efforts to blend the high school and college