O'FALLON, MO - At Fort Zumwalt West High School, class doesn't just happen in a room.

Eighteen-year-old Brendan Ritchie is a straight A student and instead of counting the days, he is trying to make every day of his senior year count.

"I'm involved on the cross country team, I run track as well. I also play ice hockey and roller hockey," he told us.

But Brendan says his best times are with his best friends.

"All of them are such nice people and I'm very blessed to call them my friends," he said.

The group has been sitting at the same lunch table for the past two years, and every day there are plenty of smiles and conversation.

Even if not all of them can talk.

Ellie McCool was born with Rett Syndrome, a rare but severe brain disorder that affects girls. She wasn't diagnosed until she was almost 4.

"She sat up on time, rolled over on time, fed herself with both hands, played with toys," says her mom Mickie McCool.

But then one day, it was like someone turned off a light switch.

"Still, she's smart and totally in there," Mickie says.

Anyone with Rett Syndrome has plenty of challenges, but Ellie's parents and friends have always kept the focus on her ability not her disability.

"She really is very bright and she is very caring and loving," says her best friend Nicole Orf.

"She's just a very happy person," Brendan told us. "She is always positive. She's always got a smile on her face."

Ellie may not be able to talk, but everybody that knows her is still talking about what happened recently in that same school cafeteria.

"I thought it was incredible," Nicole said.

You see, while many high school seniors like to think that they have all the answers, Brendan had a question.

Ellie's favorite movie is Iron Man and so Brendan showed up at school wearing wearing an Iron Man mask and in front of everybody, he asked Ellie to the prom.

"Every girl dreams of having a date to her senior prom," Ellie's friend Elizabeth Steiner pointed out. "So the fact that Ellie was going to have one too was awesome."

By the way, her answer was yes.

"She's just a really awesome girl and she deserves to go to prom with someone and I felt if it was going to be anybody, I'd like it to be me," Brendan said.

Pictures only capture a moment in time, but the pages of some photo albums turn in your memory forever.

"I was completely composed and didn't shed one tear," Mickie laughed.

That night, Ellie had her dress. She had her date. And she had her friends.

As the music played, she didn't have to leave her chair to feel the rhythm of the evening.

"It meant the world to see her so happy," says Elizabeth.

They don't teach friendship in school, but there are some who deserve high marks. As senior year comes to a close, you get the feeling that for one young man and his group of friends, this happy ending is only the beginning.

"It just made me so happy to see that she got an experience that she could remember forever," said Nicole.