Complex sentence: He attended San Pedro High School for part of his freshman year before moving to Compton, where Brenton became a member of the Compton High School track team and received several awards for his athletic achievements.
Split into simpler sentences: He attended San Pedro High School for part of his freshman year before moving to Compton. In his high school years his family relocated to nearby Compton, where Brenton became a member of the Compton High School track team and received several awards for his athletic achievements.