July 13, 1961 - About 1,800 enthusiastic foreign-exchange students turned a White House visit into a virtual stampede this morning. A White House policeman said the incident just escaped being serious. President Kennedy inadvertently set off the episode when some of the students surged forward in a pushing, shouting group to shake his hand. The students reacted as if they were movie fans greeting a matinee idol. Several were pushed down, one girl was knocked face down into a low hedge, and another fell on top of her. Mr. Kennedy beat a hasty retreat up the steps to the portico and returned to his office.