Valedictorian, Brittney Bratton, and classmates from the Youth Connection Leadership Academy attend a rehearsal for their upcoming commencement at Armour Square Park field house in Chicago on June 5, 2013. (Antonio Perez, Chicago Tribune)

Brittney Bratton made it only partway through rehearsing her high school graduation speech before she had to stop.

"Stay strong," called Danita Allen, school counselor at Youth Connection Leadership Academy as Bratton tried to collect herself. "If something is going to make you cry, think of something to make you laugh."

There hasn't been a lot to laugh about for most of Bratton's life.

Years of cooking and cleaning for four younger siblings. Physical abuse culminating in a beating so severe, Bratton says a police officer who looked at the wounds cried. A baby at 19, and no home to bring him to. A year out of school, much of it spent living in a house with no heat.

But now Bratton was graduating from high school.

As class valedictorian with a 3.9 grade-point average, the highest in the school.

And a full-ride scholarship to college.

It was enough for at least a smile.

She took a few breaths, fanned herself with the printout of her speech, and finished.

On Tuesday, six days before her 21st birthday, Bratton will deliver her speech at the commencement exercises at YCLA, an alternative high school on the campus of the Illinois Institute of Technology in Bronzeville.

She is one of 1,914 students who will graduate this year from alternative schools in the city. Youth Connection Charter School, which runs 22 of the city's 32 alternative schools, including YCLA, says its schools account for 8 percent of all CPS graduates.

Graduation ceremonies for these students are emotional affairs, celebrating victories over long odds. The average student entering a YCCS alternative high school has a sixth-grade reading level and has been out of school from five months to three years.

For Bratton, the odds once seemed prohibitive.

By her early teens, she was essentially running her South Side household, her mother having assigned her responsibility for the younger children.

"She had to take on the responsibility of cooking, cleaning, making sure the kids were ready to go to school," said her sister Briona Harris, 16. "I feel like my sister is my mother."

She was frequently beaten by her mother's live-in boyfriend, Bratton and her sister said.

"If something was spilled on the floor and it wasn't picked up, she would get beat for that," Harris said. "If a little piece of food wasn't eaten, she would get beat for that. She took a lot beatings so that the younger siblings wouldn't get beat. She would step up and say, 'I did it.'"

In middle school, Bratton did well — "School was my getaway; it was a place to get away from home," she said. But by the time she got to Lindblom Math and Science Academy, the turmoil began to take its toll.

She stopped paying attention in class. Her grades fell. She had to repeat her freshman year.

When she was 15, her mother's boyfriend beat her bare legs with an extension cord so badly, she and her sister say, that blood ran down her legs. The boyfriend pleaded guilty to aggravated domestic battery and was sentenced to 4 years of probation and anger management and parenting classes, records show.