Do the angles of all triangles add to 180°? How do we know? Has someone actually measured the angles of every possible triangle?

The area of a circle is πr2. How can an area be a decimal number that goes on forever? Can anyone measure an area that accurately? If not, how do we know this formula is correct?

Rate equals distance divided by time. That is what we mean by miles per hour. But what do I mean when I say that I am driving 60 mph right now? For instantaneous velocity, no time elapses and my car hasn't moved. So, what is my speedometer telling me?

In studying math at Commonwealth, you will learn the answers to these problems and many others. You will learn to translate real-life situations into mathematical equations and how to construct logical proofs, starting from basic assumptions and arriving at expected and surprising results.

You will learn how to picture equations with graphs and tables of values and develop intuition about their behaviors. You can study calculus and learn about limits, instantaneous velocity, and precise areas—vital to the study of physics and other sciences. You can also study statistics, which has real-world applications in the sciences, the social sciences, political discourse—and everyday life. If you enjoy challenging your creativity in a competitive environment, you can join our math team as it faces off against groups throughout New England. Regardless of the path you take through our math program, you will learn to think logically, to calculate accurately, and to solve challenging problems.

Intermediate Algebra

Do you need to work more on your algebra? In Intermediate Algebra you will start by reviewing Algebra 1, with a focus on manipulating variables with confidence and modeling word problems with solvable equations. The course then turns to the start of Algebra
2 with a full study of quadratics, rational expressions, and conic sections. You will not
just learn how to do algebra; you will also understand why it works as you develop your mathematical intuition.

Students say..."What a surprise it was—and what fun—when I began to understand that math is about so much more than a bunch of calculations and equations!

Geometry and Geometry Advanced

More than two thousand years ago Euclid wrote down the foundations of modern geometry in what is probably the most famous math book ever written, Elements. What did he get right? What did he get wrong? In Geometry you will study a modern form of Euclid’s assumptions and see for yourself what can be proven.

This course not only teaches you what is true in geometry but also why it is true. The main course focuses on geometric facts and learning to write clear proofs. If you take Geometry Advanced, you will delve into more philosophical aspects of modern mathematics. What does it even mean in mathematics for something to be “true”? Studying hyperbolic geometry will challenge your preconceptions of how the world works and bring you closer to the beauty and mystery of theoretical mathematics.

Students say..."My freshman year Geometry class was inspiring. Suddenly homework became a ‘choose your own adventure story’—each student doing work in different ways. I learned how to plan an attack on a problem, and also how to restart and try again when I had gone down the wrong path.”

Algebra 2/Precalculus and Algebra 2/Precalculus Advanced

Functions do all the heavy lifting in mathematics. In this course, you will learn to manipulate functions and represent them in different ways, from equations and tables of values to graphs. You will also study the basic panoply of common functions, from the steadfast polynomial to the transcendentals: exponential, logarithmic, and trigonometric functions. You will learn about these building blocks and how to transform and combine them into new and wonderful conglomerates. With these analytic tools in hand, you will also study conic sections, systems of equations, and (time permitting) matrices and probability.

Students say..."Some of the most thorough answers can come out of disagreements leading to a clearer picture of what’s going on. How would a math class ever progress if it were not for the student willing to point out the calculation errors of a classmate—or of the teacher?”

Calculus 1 and Calculus 1 Advanced

AP Algebra is the study of functions; Calculus is the study of how functions change. In Calculus you will learn about derivatives, what mathematicians call instantaneous rates of change: how fast an object is falling at any given time or how fast a radioactive substance is decaying (what is a half-life?). You will also study going in the other direction: if you know exactly what velocity you’ve been traveling at any given moment, how do you figure out how far you’ve gone?

Calculus 1 focuses on the theory behind calculus and real-world applications. It will prepare you for the Advanced Placement Calculus AB exam. Calculus 1 Advanced covers more advanced applications and shows proofs with more rigor.

Students say..."Where the textbook provided convoluted explanations (under chapter names like ‘A Few Simple Remarks’), my math teacher brought organization to chaos. The homework provided a necessary backdrop, but class was where explanations came together and made me want to delve deeper.”


Calculus 2

AP Here’s your chance to take what you learned in Calculus, master all the details, and then extend those results to such applications as calculating arc length and the surface area of a solid of rotation and to calculate for parametric and polar functions. You’ll learn to anti-differentiate more complicated functions and then study infinite sums. The terms get smaller, yet there get to be more and more of them. How can you tell whether an infinite sum will stay bounded or explode? This course will prepare you for the Advanced Placement Calculus BC exam.

Students say..."When I came to Commonwealth, I was not a math person. After four years of intensive math training and application in other classes, though, I have come to have a rich and abiding love for math and all of its applications.”

Calculus 2 Multivariable

AP After a review of single-variable calculus, you’ll cover infinite sequences and series. As in Calculus 2, you’ll learn to distinguish those that come to a limit from those that “diverge” to infinity. In the second semester, you will encounter multivariable calculus. Instead of derivatives, you’ll learn about partial derivatives. From the single-variable integral, you’ll turn to vector functions, line integrals, and double—and even triple— integrals. If time permits, you’ll learn about the mysteries of Lagrange Multipliers and Green’s and Stokes’ Theorems. This course also prepares you for the Advanced Placement Calculus BC exam.

Students say..."Commonwealth teaches what I call real math. And knowing what real math is like before I start college is probably going to make me a math major.”

Theoretical Calculus

AP Knowing how calculus works isn’t enough? What do the real numbers have that the rational numbers don’t? Theoretical Calculus develops all the theorems of calculus from the axioms of the Real Numbers, including the elusive Completeness Axiom. Enter the world of suprema and infima, follow the partition definition of definite integrals, and revisit old friends such as the Fundamental Theorem of Calculus.

When you’re done with the basics, you’ll use these same methods to investigate infinite sequences and series of numbers and infinite polynomials. You’ll end with an introduction to the beautiful theory of complex power series, including a quick proof of the famous Euler equation, e+1=0. Theoretical Calculus is equivalent to an Introduction to Real Analysis course in college. Some of the easier material will prepare you for the Advanced Placement Calculus BC exam.

Students say..."I never had to think so hard on an exam in my life! It was awesome.”

Abstract Algebra

Abstract Algebra is the purest of pure math courses. In this challenging, college-level elective, you will study the most fundamental of mathematical objects: groups, rings, and fields. Are there other “number” systems that mimic certain properties of the real numbers? In what ways are they the same, and in what ways do they differ? In this course, you will discover the solutions to some long-time geometric puzzles: Can one construct a cube of volume two or trisect a given angle using a compass and straightedge? You will hone your abstract mathematical skills and your ability to write clear and effective proofs.

Students say..."By ‘engaging’ in your studies, I mean throwing yourself completely into the process of learning––allowing yourself to become fascinated by a certain subject (in my case, math) and then running away with it.”

Linear Algebra

By the time you are ready to take this course, you will already have learned what vectors and matrices are and how to manipulate them. We follow an axiomatic approach to arrive at a deeper understanding of how and why they work. What is the determinant, and how is it characterized? What does a “change of basis” mean (what is a “basis,” anyway?), and why would you want to change one? This class is for budding mathematicians and those curious to know what the world of theoretical math is all about.

Students say..."I’m good at math, and it’s always fun, though before Commonwealth I’d always felt that I was essentially learning it on my own, with my textbook and homework. But being in this classroom added more than I could possibly have learned working by myself.”


How can you tell that a phenomenon is random, and what does that mean? When the newspaper reports a poll with +/- 3% after it, what exactly does that +/-3% signify? When drug companies claim that a drug will help you, how do they know, and why do scientists often change their minds later? Statistics is the study of random phenomena. In this class, you will learn how to design a study that will give you good data, how to describe the data accurately, and how to use inference to derive appropriate conclusions. The half-credit elective course moves quickly, while the full-credit course covers the same material but at a more deliberate pace.

Students say..."One of the things that surprised me the most during my project month at Harvard Medical School’s Department of Global Health and Social Medicine was the importance of having a solid expertise in statistics. Statistical analysis is a fundamental part of doing research in social medicine.”

Mathematical Logic

What is truth? How do we formalize the notions of truth and provability as objects within a formal mathematical system, and what conditions on a mathematical assertion guarantee the existence of a proof of that assertion within the system?

These are just some of the questions to be addressed in this course, a rigorous introduction to mathematical logic. We will begin with a discussion of propositional logic, including truth assignments, induction on formulas, and unique readability. We will then move on to first-order languages and predicate logic, introducing models as interpretations of languages and establishing connections between the syntactic (proof-theoretic) and semantic (model-theoretic) approaches to truth. Questions of cardinality, or size, will occupy our attention throughout the course. For instance, which theories are finitely axiomatizable? And under what conditions does a theory have models of all infinite cardinalities?

As time permits, we will examine other areas of pure mathematics, such as group theory, number theory, axiomatic set theory, and analysis, through a model-theoretic lens. Important theorems to be studied include the compactness theorem and the Lowenheim-Skolem theorem.

Mathematics Faculty

Chris Barsi

Physics and Math Teacher, Science Convenor, Robotics Team Advisor, Projects - Science Projects, Mentor
Faculty & Staff

Alan Letarte

Mathematics Teacher, Math Team Advisor, Jobs Program Coordinator
Faculty & Staff

Anna Moss

Mathematics Teacher, Projects Coordinator
Faculty & Staff

Theo Paul

Mathematics Teacher, Class Advisor 11th and 12th grade, Hancock Coordinator, Admissions Committee Member
Faculty & Staff

Jeff Racioppi

Director of Technology, Mathematics Teacher, Building Manager, Safety Co-Coordinator
Faculty & Staff

Rob Sherry

Mathematics and Economics Teacher, 11th and 12th Grade Class Advisor, Admissions Committee Member, Math Convenor
Faculty & Staff