Interactive Geoboard – Stretch Rubber Bands on Pegs

An interactive geoboard is a digital version of the classic math manipulative—a board with a grid of pegs where you stretch virtual rubber bands to create geometric shapes. It helps students explore concepts like area, perimeter, angles, symmetry, and coordinate geometry in a hands-on way.

Click on any peg to place a vertex. Continue clicking pegs to stretch the rubber band between them. Use Close Shape to connect the last vertex back to the first (creating a polygon). Click New Band to save the current one and start fresh. You can drag any vertex to reposition it, and use Undo to remove the last vertex.

Area is calculated using the Shoelace formula (also known as Gauss's area formula), which computes the area of a polygon given the coordinates of its vertices. The result is shown in square units, where each peg spacing equals 1 unit. This works for any simple polygon—regular or irregular—as long as the shape is closed.

You can create virtually any polygon! Common shapes include triangles (equilateral, right, isosceles), quadrilaterals (squares, rectangles, parallelograms, trapezoids), pentagons, hexagons, and irregular polygons. You can also create open shapes like line segments and paths. The geoboard is excellent for exploring symmetry and transformations.

Absolutely! This geoboard is fully responsive and touch-friendly. The pegs are designed to be large enough for finger tapping on mobile devices. You can drag vertices, tap pegs, and use all controls on smartphones and tablets. For the best experience on small screens, try using a 6×6 or 7×7 grid.

The geoboard supports learning in: geometry (shape properties, angles, congruence), measurement (area, perimeter, distance), coordinate systems (plotting points, ordered pairs), symmetry and transformations (reflections, rotations), and problem-solving (creating shapes with given constraints). It's suitable for grades K-12 and beyond.