Constellations
Scatter random stars, then link them by reach or nearest neighbors
Triangles Emerge
Connect nodes to form triangles
Intersections
Drag nodes along a shape and count the crossings and regions its chords make
Rainbow Triangles
Change vertex colors on triangle grids
Triangles in Triangles
Dissect triangles with labeled vertices
Graph Editor
Draw and edit graphs, snap them to grids, tap the chips to reveal structures