In Abraham Lincoln's day, most of the students were from farm families. They came to school knowing firsthand about birth and death, about the full moon, about how to lever up a heavy rock, how to sharpen a blade, and how milk soured. They didn't have to learn those things in school, because they encountered them all the time. What they went to school to learn was symbols-words and forms; how to read, write, and cipher; what scholars and leaders in the past had said; how to express and reason about the world and themselves

 Children still come to our schools with plenty of knowledge. They bring a wide visual acquaintance with the world near and far, a flood of images, fact and fiction. They see print everywhere, too; signs and posters surround them; magazines and books are commonplace, with all their pictures. Television has made the wide world familiar to children. But what is deeply missing is an inner sense of the world's real constraints, of the difference between desire and performance. Pushing a button is not like leaning on a crowbar.

 The symbols still need teaching; the three R's, the history, the maps, the tales remain urgent. But they lack any foundation beyond word and image. The schools have a big new task that they have not entirely realized: it is to bring in the hands-on world, the real uncertain thing that induces questioning, that stubbornly resists or wonderfully confirms what one does. What children need is to grow plants (and see them wilt for lack of water), to complete the cycle by planting the seed they themselves harvest from the plant they grew. They need to build bridges of soda straws that can hold up the weight of many milk cartons. They need to try which connections between bulb and battery produce light, and for how long.

 It would be an error to blame schools for our growing lack of physical contact with the physical world, but an even bigger error not to do something about it. We are all in this bind together; it is the result of a maturing technological world where production is taken farther and farther from the consumer. The capacity to judge from evidence when things are right, when they work or when they don't work, doesn't apply only to circuits or other matters of science. It also applies to political programs or to buying consumer goods. It is an understanding that begins with active experience in the natural and technological world.

 So let us teach our children how to read, write and cipher-but let us also help them explore something of how the material world works. They need to sense through hand, eye, and mind the limits of what can be done, and how even within stern natural limits new opportunities can open.

-Excerpted from the keynote address by Philip and Phylis Morrison for the National Science Resources Center's 1989 Elementary Science Leadership Institute. Philip Morrison is physics professor emeritus at the Massachusetts Institute of Technology and a member of the National Academy of Sciences. Phylis Morrison is a specialist in elementary science education.