Pencil, eraser, grid, and Paper.  :)   

-  Art pencils are great and school pencils work just fine.  
-  Any eraser will work but I recommend trying a "kneaded eraser" if possible.
-  Here is the link for grid that may be printed and used as desired.  We will talk about possible ways to use it.   https://docs.google.com/spreadsheets/d/1VUMdllWEKh49rRn_2dSCXiuuGkrGZTTPg9H1Hj4BfOA/edit?usp=sharing

-  Any paper works.  I usually use regular computer paper folded in half because that size works well for the time we have.  Drawing in a sketchbook is great too, especially the 5.5x8.5 inch size.