"I pledge allegiance to the Flag of the United States of America, and to the republic for which it stands, one Nation under God, indivisible, with liberty and justice for all."
It is said facing the flag, with your right hand over your heart. Originally it was said while saluting the flag, however, it was replaced with the hand over heart gesture during WWII, as it was similar to the Nazi salute.
Congressional sessions also open with the recital of the Pledge of Allegiance.
By the way, the words "under God" where only added on June 14, 1954.
[1] West Virginia State Board of Education v. Barnette, 319 U.S. 624 (1943) http://www.oyez.org/cases/1940-1949/1942/1942_591
I've had a few "super patriotic" teachers threaten me with detention for not towing the line. But these tended to be in urban and ex-urban, lower socioeconomic schools. The type of places that wanted to make you into factory workers rather than college students.
Of course, as I posted in the parent, the Supreme Court allows for individual students to stay seated and not salute the flag if they choose.