Join me at
Thorium For Life
Thorium For Life

Hi! I'm Mr. Stephenson.

Revised 8/14/2013

Why Math?

How to Study
Math Anything

You Can!
Make It Happen!

Do, or do not,
there is no try!

That is why you fail!

A Little Math History

Ancient Computers

Place Value ;-)

Exact Units


Why "x"?

Our Home
1, 2, 3, 4, 5, 6, 7

Big Business


Alcohol Can be a Gas!


In Defense of
The "Takers"

I retired from teaching on June 30, 2013.

Check out my Ancient Computers publications here:

(As time passes the links here will experience linkrot. Sorry.)

I taught math at Lowell High School in the Lowell Public School District, Lowell, MA, USA.
In School Year 2012-2013 (Fiscal Year 2013), I taught:
- College (1431/2)
- Honors (1441/2)

- Honors (1443/4)
    Area Under Curve by Adding Rectangles

Here are class schedules, assignment sheets, and administrative information:
Sem Periods Room Course Name Mgmt Plan
Course # Assignments 1 Assignments 2 MGB User
Both Advisory 656 Advisory
-- -- -- Advisory656
S1 1,4a,5b
656 C-Precalculus syl-CpCalc
1431 13q1aCpreCalc 13q2aCpreCalc 13s1CpreCalc
656 H-Precalculus syl-HpCalc 1441  13q1aHpreCalc 13q2aHpreCalc 13s1HpreCalc
656 H-Calculus syl-HCalc 1443 13q1aHCalc 13q2aHCalc 13s1HCalc
S2 1,4a,5b
656 C-Precalculus s2plan
1432 13q3aCpreCalc 13q4aCpreCalc 13s2CpreCalc
7 656
H-Precalculus 1442 13q3aHpreCalc 13q4aHpreCalc 13s2HpreCalc
3 656
H-Calculus 1444 13q3aHCalc 13q4aHCalc 13s2HCalc

 See grades and attendance here: 

 LHS Missed Work Make Up Policy  Absence Policy

GeoGebra: Free mathematics software for learning and teaching

Microsoft Excel Spreadsheet Tutorials

Khan Academy: Free Videos and Interactive Math Exercises from Arithmetic to Calculus

The Calculus Lifesaver: All the Tools You Need to Excel at Calculus
by Adrian Banner, Princeton University
Free Video lectures


Updates from here down are infrequent and sporadic.

A High School Math Reference (
My notes on the "why", "how", and "what" of selected high school math concepts.

Above link no longer works since Google took down the Knol system -- I'll fix it eventually.

Old Course Links


A Straight Line: From Geometry to Algebra   
Derive the equations of a straight line from similar triangles.

Special Lines (Horizontal, Vertical, Perpendicular, Parallel, Identical), Distance, & Midpoint   

Essence of Basic Transformations  

Remainder Theorem, Synthetic Substitution, Synthetic Division  

Inverses: From the Basics  


Blitzer Checkpoint Movies


Foliage Trip     
Introduction to Derivatives, Integrals, and the Fundamental Theorem of Calculus.

Lab: The Tangent Line Problem   
Introduction to limits for differentiation.

Lab: The Area Problem   
Introduction to limits for integration.

Larson: p48, Introduction To Limits   

Larson: p49, Example 1, Estimating a Limit Numerically   

Larson: p56, problem 47  

Course Handouts

Graphing Rational Functions  

Other Stuff

You're going to college; so what high school math is really important, what will the colleges expect that you know? How do you prepare for the math placement tests you'll have to take? (If you don't pass the math placement tests, you'll have to take, and pay for, remedial math classes that don't count toward the requirements of your major.)

See Exercises in Math Readiness for University Study.

For a list of useful and interesting math web sites click here. (Updates sporadic.)

Past MCAS tests

Massachusetts Math Framework Learning Standards:

Algebra 1 (pre-requisite for both Geometry and Algebra II)


Algebra 2


4/5/2008: I've just found a wonderful alternative to Geometer's Sketchpad; get it here:

The two main advantages to GeoGebra are: 

  1. it's FREE for everyone; and 
  2. it integrates geometry and algebra, and even some calculus.

My first attempt is All Conics from One Directrix, which I could never get to work in Geometer's Sketchpad, but was easy in GeoGebra.

I intend to use GeoGebra exclusively from now on, and to convert my existing Geometer's Sketchpad constructions to GeoGebra as time permits.

The Tangent Problem


Conic Sections

Paper Folding and Applications of Conic Sections  
by Bruce Yoshiwara, Professor of Mathematics, Los Angeles Pierce College

All Conics from One Directrix


Elimination vs. Augmented Matrix Row Operations:


Remainder Theorem and Synthetic Substitution/Division:

Polynomial Root Theorems:

Pascal's Triangle:

Area and Volume

Volume and Area of a Sphere by Cavalieri's Principle:


Derivations of Derivatives


Trig Functions 

Other Functions 

Paper Calculator:  

Math Reference Sheets: MCAS: ; MCAS-like:

Grid Paper Generator

Grid Paper:  

Isometric Dot Paper: ; Isometric Line Paper:

Table of Common Logarithms:  

Counting Board:

Graphing Calculator Help

TI calculator Guide Books


Triangle Concurrency Points: Video, Sketch.

All Conics from One Directrix: Video, Sketch

Area of Trapezoid Inscribed in Semicircle: Sketch

Java Applets

Parabola: Vertex Form, Standard Form

Geometer's Sketchpad (version 3) files and Files:

Tree Height

Classroom Files on the Web

Geometer's Sketchpad (version 4) files and Files:

A Triangle Within a Triangle, Lab Project Instructions

n-gons, n = 3, 6, 12, 24, 48, 96;  96-gon looks like a circle!

KillBird (Projectile Motion)

Java Applets:

Triangle Angles, Lab Project Instructions

2001-2008 by Stephen Kent Stephenson. All Rights Reserved.