Coding lends itself to creating art together. Lets try the following -

Circle / Triangle / Rectangle

Each person in the group executed a single step (circle back step 1 after step 4)

1. Draw a rectangle
2. Draw a circle whose - Center = any corner of the rectangle - Radius = any side of the rectangle
3. Draw a triangle, whose base is tangent to the circle, and the point of tangency is the midpoint of that side
4. Draw a rectangle using any side of the triangle. Repeat 1-3, without overlapping any previous shape

Added conditions :

Draw in Warm colours for even roll numbers and Cool for odd roll numbers If your first name contains any of the letters A, L, P, S or K, draw in thick lines If your turn to draw is a multiple of 5, fill in the shape If your turn to draw is a multiple of 3, make the fill 50% opacity