This cardboard die was made in an attempt to settle disputes in our house. My youngest had just turned two, and well, no dice, it didn't work at all. The two of them actually fought over who got to play with the cube, so I just put it on my shelf, and chalked it up to a failed experiment.
At two and a half though, things have changed for the better, and the "turn cube" is doing me some justice.
Just a cardboard cube, six photos and assorted washi tape is all that you need. If you have an odd number of children in your family, you'll need to put a "roll again" message on one face of the cube, and if you have more than 6 kids, well, I'm sure you've figured out a better system than this for maintaining your sanity!
For instructions on how to make the cube, you can find them here, in the book I sell in my Etsy shop. The pattern also explains how to make large cardboard blocks that you can take apart and store flat, a really cool design.
Otherwise, try a plain cube-shaped cardboard box, often the ones that ornaments come in at this time of year are perfect!