Background: Yelberton Abraham Tittle Jr. (October 24, 1926 - October 8, 2017), better known as Y. A. Tittle, was a professional American football quarterback. He played in the National Football League (NFL) for the San Francisco 49ers, New York Giants, and Baltimore Colts, after spending two seasons with the Colts in the All-America Football Conference (AAFC). Known for his competitiveness, leadership, and striking profile, Tittle was the centerpiece of several prolific offenses throughout his seventeen-year professional career from 1948 to 1964. Tittle played college football for Louisiana State University, where he was a two-time All-Southeastern Conference (SEC) quarterback for the LSU Tigers football team.
Context: Born and raised in Marshall, Texas, to Alma and Yelberton Abraham Tittle Sr., Yelberton Abraham Tittle Jr. aspired to be a quarterback from a young age. He spent hours in his backyard throwing a football through a tire swing, emulating his neighbor and boyhood idol, Sammy Baugh. Tittle played high school football at Marshall High School. In his senior year the team posted an undefeated record and reached the state finals.  After a recruiting battle between Louisiana State University and the University of Texas, Tittle chose to attend LSU in Baton Rouge, Louisiana, and play for the LSU Tigers. He was part of a successful 1944 recruiting class under head coach Bernie Moore that included halfbacks Jim Cason, Dan Sandifer, and Ray Coates. Freshmen were eligible to play on the varsity during World War II, so Tittle saw playing time immediately. He later said the finest moment of his four years at LSU was beating Tulane as a freshman, a game in which he set a school record with 238 passing yards. It was one of two games the Tigers won that season.  Moore started Tittle at tailback in the single-wing formation his first year, but moved him to quarterback in the T formation during his sophomore season. As a junior in 1946, Tittle's three touchdown passes in a 41-27 rout of rival Tulane helped ensure LSU a spot in the Cotton Bowl Classic. Known notoriously as the "Ice Bowl", the 1947 Cotton Bowl pitted LSU against the Arkansas Razorbacks in sub-freezing temperatures on an ice-covered field in Dallas, Texas. LSU moved the ball much better than the Razorbacks, but neither team was able to score, and the game ended in a 0-0 tie. Tittle and Arkansas end Alton Baldwin shared the game's MVP award. Following the season, United Press International (UPI) placed Tittle on its All-Southeastern Conference (SEC) first-team.  UPI again named Tittle its first-team All-SEC quarterback in 1947. In Tittle's day of iron man football, he played on both offense and defense. While on defense during a 20-18 loss to SEC champion Ole Miss in his senior season, Tittle's belt buckle was torn off as he intercepted a pass from Charlie Conerly and broke a tackle. He ran down the sideline with one arm cradling the ball and the other holding up his pants. At the Ole Miss 20-yard line, as he attempted to stiff-arm a defender, Tittle's pants fell and he tripped and fell onto his face. The fall kept him from scoring the game-winning touchdown.  In total, during his college career Tittle set school passing records with 162 completions out of 330 attempts for 2,525 yards and 23 touchdowns. He scored seven touchdowns himself as a runner. His passing totals remained unbroken until Bert Jones surpassed them in the 1970s.
Question: At what age did he start playing football?

Answer:
Tittle played high school football at Marshall High School.