When we teach about composition there is a trick to making the explanation clearer. Tease out the elements of composition and teach about them one at a time.
Use coloured card to show examples of the different elements and how they would look. For point you can use confetti, rice or some other scatterable spread. For lines perhaps string, straws, coloured cord or skewers.
Perhaps you could tear the coloured card into pieces, or cut it, use confetti and sprinkle it on. Play with composition by pushing, pulling, mixing and matching until the pieces sit comfortably together. Glue them down as collage or take digital photos and project them on to the wall.
Much of this learning is about aesthetic choice and personal taste.Appreciative Inquiry will show students that there will probably be a group consensus about what feels right when evaluating colourful compositions.
Look at these aspects of composition separately
Composition is about how things sit and how they react with each other.
Not always but mostly there will be a focal point for the composition.
Not always but usually there will be some structure around contrast between bunched up space and sparsity
When we teach about composition it is important to remember that students often learn best by exploring. Group work can be fun and productive.
Students need to feel free to
Don't forget to include texture
If you would like to look at some interesting examples of composition using line, tone and texture look at Dr. Zeus' Drawings Broad-tip Pen.
If you would like post your work to the discussion boards I would be happy to give feedback.