- Geogebra Material
- Exterior Angles of Polygons
- Area of a Circle - Wedge/Sector Demonstration
- Dudeney's puzzle + lesson plan
- Unit Circle and Sine Graph
- Circumference of Circles
- Unit Circle and Tangent Graph
- Linear Programming
- Unit Circle and Cosine Graph
- Slopes of Perpendicular Lines
- Cut Triangles into Rectangles & Dudeney's Puzzle Generalized
- Chinese Match Puzzles 1 (8 puzzles)
- Chinese Match Puzzles 2 (7 puzzles)
- Largest area enclosed by 16 matches
- Matrix and Linear Transformation
- Incircle of a triangle
- Circumcircle of a triangle (Soft Construction)
- Constructing Quadrilaterals by Four Sides (2014)
- Ambiguity of SSA
- Area of Parallelograms (GeoGebra 4 version)
- Discovering Pythagoras' Theorem by Area
- Drawing Rhombus on the Grid
- The touches of y=a^x and y = log{a} x
- Geometry and Operation of a Sextant
- Who Gets the Charger
- Inverse of a Function (graphical and numerical)
- Understanding Graphing Polynomials through Geogebra
- Exponential Functions
- Stadium Screen Viewing Angle
- Circle Geometry - Intersecting Chords
- Girl in the Mirror
- Further Transformations of Cosine Functions
- Further Transformations of Sine Functions
- Sine Transformations: Graph, Equation, Table
- Transformations of Functions
- Trig Inverse Functions
- Defining Trigonometric Ratios
- Double Reflection of an object
- Equations of a circle - Self Discovery
- Rotating a Triangle Around a Coordinate Axis
- Area of Circles
- Vertex Form of Parabola
- Ambiguous Case Investigation
- Circumcenter
- Visual Proof of Pythagorean Theorem
- Parallel Parking optimization (US customary units)
- Area Under the Curve
- Using Riemann Sums to Estimate Area
- Trapezoidal area approximations 2
- Simpsons Rule
- Dissecting a triangular prism into 3 equal-volume pyramids
- AA Similarity
- Nine point circle
