What are the largest high schools in the US?

In the early 70s a school was built called Thornwood in South Holland Ill. a sister school to both Thorton and Thorn Ridge. Thornwood at the time of completion was the 10th largest school in the nation holding over 4000 students. It has grown since then and Im sure holds many more along with its sister schools

Plymouth-Canton Education Park in Canton, Michigan. I'm pretty sure it is the largest. I go there and we have 3 schools. Salem High School, Canton High School, and Plymoth High School; all are located on one campus. Students are assigned a "home school" for sports reasons, but you can have classes in all three schools. Like me, Salem is my home school, and freshman year, I had my first 3 hours in Salem, then I walked over to Canton, then after Canton I walked to Plymouth (which is the longest walk and the reason we get 10 minutes passing time. Sometimes people have to run to class depending on where their classroom is). Then after Plymouth, I walked back to Salem. I'm going to be a senior this year (2010-2011) and we have over 6,300 students in the Park (that's a nickname for it. Also commonly known as P-CEP [pronounced pee-sep])

I hope this helped. It's a really unique campus and I absolutely LOVE every minute of it.