Lessons not in a Unit  
 Circumference of the Earth 
This lesson focuses on using the estimation of the circumference of the
earth to reinforce basic geometric properties of circles and parallel lines.
The lesson continues with using Eratosthenes method to estimate the
circumference of the earth.

 Introduction to Negative Numbers 
This lesson introduces the student to negative numbers using the
concepts of magnitude and direction in both visual and kinesthetic
frameworks.

 Adding And Subtracting Negative Numbers 
This lesson helps the student to understand the meaning of adding
and subtracting positive and negative numbers.

 The Pythagorean Theorem 
This lesson plan teaches the students to discover and write proofs in
the context of the Pythagorean Theorem. The Chinese proof of the
Pythagorean Theorem is used, as it is more accessible to children
in grades 712.

Introduction and Review for Intermediate Algebra 
This unit is intended to review foundational concepts for an Intermediate Algebra class. This unit is designed for 10th grade intermediate algebra students.

 Visualizing in Mathematics 
This lesson reintroduces the various methods of visualizing in mathematics. It introduces the student to 3D visualizations.

 Adding and Subtracting Positive and Negative Numbers 
This lesson reviews adding and subtracting positive and negative numbers.

 Properties of Real Numbers 
This lesson reviews the properties of real numbers, including associative, commutative, distributive, and absolute value.

Modeling With Algebra 
The unit starts with the concept of using math to model realworld situations, then explores the use of functions, matrices, and simulations as modeling tools. This unit is designed for 10th grade intermediate algebra students.

Introduction to Geometry 
This unit is an introduction to Geometry with and emphasis on mathematical
reasoning and proof.

 Properties of Lines and Points 
This lesson plan teaches the properties of lines and points within the
discipline of Geometry. It focuses on mathematical reasoning and introduces
the students to the rigors of proof.

Math Logic 
This unit is an introduction to math logic starting with concepts students
can understand.

Fractals 
A Fractals Unit for Elementary and Middle School Students by Cynthia Lanius, Dept of Mathematics, Rice University.

Spy Science 
This unit is intended as an afterschool enrichment program for students in the 4^{th}
to 6^{th} grades. It uses the subject of spying to explore human behavior, encryption,
chemistry, optics, audition, observation, and using the Internet as a resource.

 Introduction to Spy Science 
This lesson is intended to frame the course and motivate the students to complete the unit. It answers
such questions as, "What will we do?", "Is this going to be fun?", and "Can I really use the things I learn here?"

 Introduction to Encryption 
This lesson is a gentle introduction to encryption. It starts with the concept of 'secret code',
accessible to most preteens, and uses it to introduce the vocabulary and basic concepts of encryption.
