Gallery
Discover apps people built on Collabby by chatting. Run them, then remix to make them yours.
3D Coordinates and Space Figures
Place points with three coordinates, apply the Pythagorean theorem twice to measure distance in space, and see how equidistant points form a sphere.
Conics: Ellipse, Parabola, Hyperbola
Drag points to see how a constant sum or difference of distances to two foci, or equal distance to a point and a line, produces ellipses, parabolas, and hyperbolas.
Volume and Surface Area of Cuboids
Change length, width, and height to stack unit cubes for volume, then unfold the box to work out its surface area.
Classifying Triangles and Quadrilaterals
Change angles and vertices to see how triangles and quadrilaterals are named by their properties, and how those names overlap.
Triangle Congruence Conditions
Pick SSS, SAS, ASA, AAA or SSA and drag the sliders to see whether the triangle is uniquely determined or several different ones appear.
Platonic Solids
Rotate the five Platonic solids to count faces, vertices and edges, and check that V-E+F=2 always holds.
Interior Angles of Polygons
Split polygons into triangles to see why the interior angles add up to 180°×(n−2), then work out one angle of a regular polygon.
Circles and Pi
Roll a circle to measure its circumference and compare it with the diameter to discover that pi is always about 3.14.
Area of Shapes
Cut and rearrange parallelograms and triangles into rectangles to discover the area formulas yourself.
Symmetry in Shapes
Color one side and watch the other fill in across the axis to learn line and point symmetry.