Category: Teachers

Professional Development for teachers

Math as a Laboratory Science

Math is not only the last letter in STEM or STEAM, it is the only one that we do not picture as experimental. We don’t imagine students learning science without doing experiments. We don’t imagine them learning technology without writing code, or learning engineering without building models, or learning art without messing with paint, clay, or paper. Yet, we easily imagine learning math without experimenting. In fact, it is rare that students ever do a math experiment or think about math that does not have a “right” answer.

I learned to experiment from one of my great teachers, Walt Hunter. I even had the great good fortune to also being his chemistry lab assistant my senior year in high school. That I did not fall in love with chemistry was not his fault; I had just loved physics since I was 7 years old. But I did fall in love with experimentation, and like Walt I gained a deep belief that learning to experiment should be an essential aspect of every student’s education. I brought that belief to my physics classes replacing teacher demonstration with student experimentation. I took it to my Jr. High math classes, where I made my students worksheets that let them play with numbers and mathematical patterns. I carried it to my focus on manipulatives as a math coordinator, and I bring it to What if Math.

Using spreadsheets as basic learning tools for math has many advantages, but I think the most important one is that it turns math into a laboratory science. It enables students to experiment, to build and iterate models, to test those models, and to apply them to real-world data, complex rich data. It lets them ask and answer what if… questions. And it turns them into explorers who love to use math and who gain Walt’s experimental habits of mind, the thrill of discovery. It is this, I now know, that Lynn Steen saw when he described mathematics as the “Science of Patterns,” for math does belong to STEM/STEAM after all. So, when you plan your math classes, imagine your chemistry teacher, and the twice weekly labs where you learned to act like a scientist, to explore, to discover, to ask, “What if…”

Art

*Portrait of Antoine-Laurent Lavoisier and his wife by Jacques-Louis David, ca. 1788, Wikipedia

What Algebra?

Each summer, as schools get ready for a new school year, the question returns, “Should we be teaching algebra to our children?” it seems to have been started by Andrew Hacker who has tried to argue and continues to argue that algebra is both difficult and an unnecessary burden for most of our students, and thus should be dispensed with. He continues to ask and the echo continues to resound, but they focus on the wrong question. The question should not be “Whether algebra?” but instead must be “What algebra?” For there are many algebras, but in particular we should focus on two, the algebra of solving equations and the algebra of functions.

Most of the algebra we teach our students is the algebra of solving equations for unknown quantities. Its origin dates back almost 1300 years to the Muslim flowering. It is the algebra we are all familiar with using x as the sign for the unknown quantity and the collection of techniques for finding out what x is equal to. Its fundamental methods, balancing and completion, are found in the title of the great work from Al Khwarizmi from which its name derives. Today it has become little more than the practice of manipulating symbols for the problems that it was designed to solve are no longer the primary problems of the business community which stimulated its practice.

The other algebra that we trace directly back only 500 years to the late 1630’s is the algebra of functions. This algebra does not solve equations, it builds tables and graphs; it is not about unknown quantities, it is about variables, quantities that can and do take on multiple values; it relies not on a series of paper algorithms, but on dynamic engines that graph and change. It is, in sum, not a static algebra but a dynamic algebra and thus the algebra of science. And of most importance, it is the algebra of spreadsheets making it today, the algebra of business too.

The algebra of functions need not and does not rely on the algebra of equations as a foundation, particularly in this time of computers where spreadsheets automatically compute. It does not need the mechanical skills of solving specialized forms of equations, nor the conceptual confusion of this x thing called by the algebra of equations “a variable” but in reality a placeholder for an unknown number. Introduced in schools today as a modest extension of the old algebra for most students, the algebra of functions only makes a serious appearance for those planning to take calculus. Despite its importance in business today, the algebra of functions and their spreadsheet tools are not a significant part of our standard math curriculum even in college algebra courses where the paper and pencil mechanics of functions are studied but not, not their applications. It is no wonder that our students complain so bitterly that the math they are forced to learn is abstract, meaningless, and utterly useless.

We should not be asking whether we should be teaching algebra, we should be asking “What algebra should our students be learning?”

To learn more you may want to read my paper, The Idea that Changed the World.

Personalized Learning

These two words have caught the imagination of educators and parents. They were designed to be the frames for talking about the value of digital learning. They were to replace the bland “individualized learning.” They were meant to symbolize a focus on the student, student-centered, and on that great American tradition, individual freedom. What surprises me is how we can attach so importance to this idea of personalization of learning and at the same time accept a common core curriculum, so dominating that it today takes up most of the school day.

The core of an apple is maybe 1/5th of its width, and if we square it to get its area 1/25th or cube it to get its volume, 1/125th of the whole. So if there is core knowledge, which it is argued, has to be at the foundation of what every student should know, and if we believe that learning should be individualized, then shouldn’t that core knowledge be a very small ratio to the whole? Shouldn’t core learning make up only a tiny portion of the school day? Shouldn’t we redefine core curriculum if we have any hope of making learning a personalized affair?

Because personalized means that a student has choices. It means that what, as well as how, a student learns and certainly why a student learns, must be the student’s choice. It must fit their interests as well as their abilities. We have always known that students have to be motivated to learn, they have to care to pay attention, pay attention to concentrate, and concentrate to learn. So, in fact, learning can’t be forced or required. It can’t be mandated. Learning has to be wanted which is the reason, the fundamental reason, it has to be personalized.

So let’s go back to work and define a core curriculum that represents the true core of the learning apple. The core curriculum need not follow the apple 1/125th model, that would most certainly be too stringent. But we should expect it to be reasonable. Core knowledge in the 21st century is changing every day and is easily searched for. Core skills on the other hand, 21st century skills, are sure to be necessary for as far into the future as we can see. Shouldn’t our curriculum reflect that? Shouldn’t the Math Common Core flip the importance and thus the time and priority between the Standards of Practice and the Standards of Content. For only then will we engage our students, personalize this their dreams, and really prepare them for 21st century work and life.

Function Machines

I do not know who, when, or where this iconic mathematical representation was developed. It is, however, one of the most powerful and ubiquitous of all mathematical images, and I think the most important. It is taught to 2nd graders and used by STEAM professionals. It is called a function machine, and it represents the way we think about change, cause and effect, and technology as well as mathematical functions. For since the dawn of the industrial age we have pictured our world as a machine, as a “rule” that converts (connects) an input into an output.

Watt Machine in B&WThis image of James Watt’s early steam engine shows a variety of inputs, outputs, and connections between them. On the left side, the steam from heating water provides the input to the rule, the big piston outputs the steam into the vertical motion of the piston. That vertical motion, through the rod connecting the piston to the lever, is now a new input. The lever is a rule changing the direction of the motion connecting it to a wheel on the right side. This rule converts vertical motion to circular motion. The lights lines are belts to link the circular motion, yes a link is a rule to drive some other outputs, one of which is the governor. The governorFunction Machine, that diamond shaped object with two balls attached in the middle of the diagram controls the speed of the engine spreading as it speeds off to reduce the steam output slowing the engine or narrowing to let more steam speed it up. Feedback enables a rule to modify the input based on the output.

These are just a few of the functions that make up this function machine, converting heat to steam to drive a piston, to turn a wheel, to add more water, to… The function machines we build on spreadsheets work in the same ways, sometimes just multiplying a quantity, sometimes changing one form of data, or sometimes using the output to control the input. Though we may think about different things today than people did 300 years ago, we still build our ideas in much the same ways. We still build models as collections of functions.

Stand and Deliver

It was an appropriate title for the movie about Jaime Escalante and it is an appropriate title for the role that teachers continue to play. We all too frequently see our role in both K-12 and in college as an actor standing and delivering. As problematic as that vision may be for our physical classrooms today, it is even more of a problem for digital learning classrooms. It is the reason that the most common refrains we hear about teaching online is how much harder it is, how much more time it takes, how difficult it is to keep connected with students. For we have taken the stand and deliver classroom model and transmogrified it into the online model.

AkenatonStand and deliver teaching puts the educational burden on the teacher. Students are the recipients of the knowledge in the head of the teacher. I am reminded of this old Egyptian image of Akhenaten’s god. In the paper classroom the teacher’s ability to motivate, to tell a story, to organize, and to simplify the textbook’s knowledge was nearly all of the content available to students. Stand and deliver was a reasonably efficient way to bring the content to the student. Eye contact, proximity, raised hand signals, and easy verbal interaction made this model sufficiently flexible, engaging, and rewarding.

But stand and deliver in the digital classroom without eye contact, proximity, or easily recognized hand signals requires us to rely on other means to hold the engagement of students or to recognize their learning signals. A number of tweaks have been tried to make the model work. MOOCs make their video lectures less than 7 minutes long and separate them with student activities. Teachers make themselves available 24/7 to talk online with individual students. New communication and presentation formats have been tried to enable students to engage with each other as well as with the teacher. Teachers have to provide a wide variety of additional materials and different formats to accommodate student needs. But if technology is to enable a more valuable and efficient learning experience then we must think anew about its use and let go of the thousand-year-old stand and deliver model.