Sine of the Times https://validator.w3.org/feed/docs/rss2.html Catching the Vibe Exploring Triangle Area with Custom-Built Tools Constructing an Ellipse with Web Sketchpad Tools Putting the Power of a Point Theorem to Work Pythagoras Plugged In Make Your Own Fractions The Varied Paths to Constructing a Square Digging Deep Into Varignon’s Theorem Deducing the “Mystery” Fraction A Geometry Gem from Twitter Interactive Array Explorations The Scaled Maps Problem A Dynamic Approach to Finding Pirate Treasure Circle Tracer Challenges Dividing and Subdividing The Folded Circle Construction The Expanding Circle Construction Tweaking the Expanding Circle Construction Constructing the Pi-Petal Rose Visual Models for Adding and Subtracting Fractions Pirate Treasure Awaits Race to the Burning Tent The Cowgirl Problem Symmetry Challenges A Paper Folding Investigation from Connected Geometry Euclid Walks the Plank Special Quadrilaterals and Their Diagonals Slope of the Sine Function, Part 1 Slope of the Sine Function, Part 2 A Transformations Approach to Complex Numbers A Compendium of Elementary Web Sketchpad Activities Teaching with Web Sketchpad Classifying Quadrilaterals Tracing the Sine and Cosine Functions Exploring Conic Sections with Sketchpad Constructing Rectangles with Constant Perimeter and Constant Area A Trio of Parabola Constructions A Plethora of Hyperbola Constructions Some Triangle Shearing Investigations A Quartet of Ellipse Constructions Protect the Sheep Drawing an Ellipse with Pins and String Drawing Ellipses with a Congruent Triangle Construction A Beautiful Application of Shearing Experiments with a Color Calculator Rotation Designs Visualizing a Dynamic Triangle Modeling with Dynamic Algebra Tiles Drawing Conic Sections Point by Point Building with Pattern Blocks