They were such a cool class, those sixth-graders. To us fifth-graders in 1971 at St. Mary of the Assumption Elementary School in Herman, they were bigger, faster, more mature, more sophisticated, learned.

Our teacher was a history buff. Their teacher taught mathematics.

History is soft -- always looking through the rear-view mirror. Mathematics is edgy, forward-looking -- pushing the envelope.

Our class would switch classrooms with the sixth grade a few times each week. This enabled us to peek into their world. It was great. They had the use of a large wooden triangle, a large straight edge, and even an oversized compass that, if manipulated properly, could form perfect circles on the blackboard.

Our fifth-grade classroom had pictures of presidents. Sixth grade had formulas and geometric shapes that inspired the imagination. Even their art projects had a mathematical connection.

An "assignment" was given to the sixth-graders. Studying the subject of "volume," the task was to make a model of a geometric shape that could help the class understand three dimensions (volume) as opposed to two dimensions (area).

Weeks passed, and then, my fifth-grade colleagues and I entered the classroom on a sleepy-eyed morning for our math class and there it was -- the most awesome mobile ever seen at our school in Butler County (or any elementary school for that matter).

The shapes, formed using art board, hung from a lateral support that was suspended from the ceiling. Those shapes -- the sphere, the pyramid, the cube and others -- were simply huge but in perfect scale with the classroom.

The shapes were a simple white color. The quality of the construction was so exact that the entire structure seemed to have been purchased from a professional model maker -- a faceless company -- not hand-made at someone's dining room table. None of the other models could compete with its grandeur.

Word got around that Rita H. had made the mobile. Her father, it was rumored, had helped. They brought the mobile into the classroom and suspended it from the ceiling the evening before.

I was simply mesmerized by this sculpture. It commanded my attention each time I entered the classroom or simply passed by the door.

How was it made?

What tools were used?

How did they get the corners so exact?

I had heard the word craftsmanship before -- this must be it. The mobile was, in a word, beautiful.

Forty years later I still remember how that mobile affected me.

In his recent book "Why Architecture Matters," Paul Goldberger writes, "Architecture is the making of place and the making of memory."

I had no way of knowing, as a fifth-grader, sitting at my desk staring up at that mobile in the fall of 1971, that one day I would become an architect and that the study of architecture would be such a large part of my life.

What mysterious events steered me along that path? There were many I suppose, but none that I remember as vividly as being in that classroom staring up at that mobile -- the mobile that Rita H. and her father made for her sixth-grade mathematics project at St. Mary of the Assumption Elementary School so many years ago.

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