Empire State Building
http://www.esbnyc.com/kids/kids_faq.cfm?CFID=5998574&CFTOKEN=37502286
This is the official site of the Empire State Building that has a special kids section that gives the history and the dimensions of this landmark.

Erie Canal
www.nyscanals.gov/cculture/history
A brief history of the Erie Canal, a canal that helped western migration and made NY State a center for commerce.

New York State
http://www.dos.state.ny.us/kidsroom/menupg.html
This is the official New York State site that has history, the state seal and other symbols of the Empire State.

Statue of Liberty
http://www.nps.gov/stli/mainmenu.htm
This is the official site of the Statue of Liberty which gives information on the history of the landmark plus statistics about its size.