I use small visual references for the younger students and to jog the memories of the older ones.
After finishing my charts, I realized that I probably should have used the word "last" instead of "then", so I have made two different copies of these files which I have in PDF form for you to use. You can find them on my Google Docs account: https://docs.google.com/?pli=1#folders/0BzoMq-hdXv6tNGQ4OWQ5ODYtZGZkMS00YzIxLWFhNGYtNDY4OTljNDBjZjdm
(Note: Blogger is really acting up lately- I couldn't link the way I would normally. Sorry!)