Any kind of ball at all, Debbie. I think we will have fun and learn from one another.
A lot of craft stores have paper mache' balls which I love. BUT they are for under the patio in bowls etc because even with sealer, they don;t do well getting wet. Ask me how I know.
But, that being mentioned, I love a large clear glass bowl with colorful mosaic or painted or ??? balls stacked in it.