Here are two good blog posts of note dealing with American Presidents.
The first is Anniversary of Lincoln's first assassination attempt. It is from 2005 and it is by Norma Bruce. It has information on Lincoln's first assassination attempt which was foiled by a librarian who was his body guard. Got to love those hero librarians like William T. Coggeshall.
The second is by elementaryhistoryteacher. It is George, We Hardly Knew Ye! It deals with how she teaches elementary school students about President Washington including dispelling myths about him. (What, no wooden teeth!)