Elbridge S. Brooks 
The True Story of Christopher Columbus, Called the Great Admiral [PDF ebook] 

Great book for homeschool history.
We all know the basic story of Columbus and the three ships this expands and tells you the rest of his life.
The author points out that Columbus was encouraged to head south and follow the parrots flying instead of sailing straight which would have landed him on the coast of America instead of ending up in Cuba. This could have resulted in Span settling America with a totally different history!!!!!