GEARS

SPINNER

RAMP

؜Tunnels

Cardboard Tubes

Half Cardboard Tubes

Wall Maze

Make sure to have wide strips

Windmill Obstacle

You could place this element perpendicular to the obstacle or in the same direction as your ball course

Inclined Planes

Add pins to secure the ramps, you can add triangle support at the center of the ramp for support

Funnel

Cut the end

You can use cups as well!