Tennis isn’t just a sport for Caitlyn Williams, it’s a passion. So much so that she switched from public school to home schooling just to have more time to play.

Traveling around and playing in tournaments was taking her out of the classroom, anyway.

“I missed 47 days of school last year,” Williams said. “Tennis is a big part of my life.”

The latest stop on her busy schedule is Norman, where she’s competing at the USTA 16-and-under National Open at Westwood Tennis Center. The event began Saturday and concludes Wednesday.

The singles finals will be today, starting with semifinal matches at 8 a.m. The championship matches will be at noon.

Williams, from Knoxville, entered the tournament as a No. 2 seed and has lived up to the ranking. She’ll face fourth seed Alicia Kauss of Overland Park, Kan., in today’s semifinals. Williams is no stranger to Kauss.

“I’ve played her a couple of times. She’s really smart and she’s a really good player,” Williams said. “I beat her a couple of times in three sets, but she beat me most recently.”

The other semifinal match features No. 1 seed Jasmine Minor of Mundelein, Ill., against No. 9 seed Nicole Flower of Columbus, Ohio.

On the boys side, No. 2 Omar Aly of Tulsa will face No. 4 seed Robert Verzaal of Shreveport, La., while No. 9 seed Mathew Zachary of Bossier City, LA., will play third-seed Michael Grant of Santa Barbara, Calif.

No. 1 seed Cale Hammond, who won a state championship May 10 at Bishop Kelley, was beaten by Zachary in the third round.

Williams already has a championship, teaming up with Megan Kurey to win the doubles crown Monday. They beat Kauss and Mimi Fotopoulos 8-4.

Williams has won a pair of titles in the past year, winning a national event in Baltimore and a regional tournament in Texas. But she’s so focused on her game, she doesn’t worry about winning trophies.

“Winning is good but every match I play, I’m just trying to get better and better,” she said. “I just focus on the things I need to work on and try to improve.”

Most of the time, Williams isn’t even aware of the competition. When she is, it’s usually by accident.

“My mom doesn’t let me see the draw,” she said. “She wants me to be in the right frame of mind when I go into a match. Sometimes the draw is just out there and I can’t help but see it. My mom will tell me who I’m playing, so there’s no point looking ahead.”