5:09 p.m.: See and hear more of what O'Ree had to say in this video:
2:28 p.m.: Here's a video from this morning's event:
But stepping across that racial boundary wasn't the toughest thing he had to face on the ice, he said after speaking with students inside the Charter High School for Applied Technologies this morning.
O'Ree (photo by Harry Scull Jr./Buffalo News) was blind in his right eye after a slap shot shattered his retina before he made it into the league. A doctor told him he would never play hockey again.
But he persevered, telling himself to "concentrate on what you can see." Aside from his younger sister and a teammate, nobody ever knew he was blind in one eye while he played hockey.
O'Ree, who is part of the NHL's youth development program, brought a "stay in school" message to students.
"You can make things happen," O'Ree said, "and you can make a difference."
Check back soon for a video from this morning's event.