If you are not using the interactivity, perhaps you could find three differently coloured balls, counters or cubes to try out some ideas. Or you could just use coloured pencils and draw three spots.
If red landed in the middle, how could the blue and green fall? Where else could red land if it wasn't in the middle? Can you use this idea to find all the ways?
Vincent and Tara are making triangles with the class construction set. They have a pile of strips of different lengths. How many different triangles can they make?