Jim Rota took the standard periodic table of the elements and broke it into 12 columns to make it easier to understand.
There are several unique structural things about the Rota Period that make it easy to understand and use:
1. It uses 12 columns (groups).
2. The 5+, 6+, 7+, and 8+ elements are not classified into groups V, VI, VII and VIII (or IUPAC 5, 6, 7, 8). This gives these elements their own unique position in the periodic table.
3. It uses the horizontal and vertical of the page to displace elements. This allows ALL elements to have a unique position (if/when necessary).
4. It is based upon showing valences, not orbitals.
Which makes it easier to understand if you know more about chemistry than I do. He sent this in response to my humor post about chemistry at Miss Cellania, but I knew it would find a wider audience here. Link -Thanks, Jim!
There is nothing like the tried and true:
http://www.touchspin.com/chem/DisplayTable.html