Heath graduated from Ridge High School in Basking Ridge in 2006, where she played soccer for three years. She also played for the 2003 Club National Champion PDA Wildcats team. Heath was ranked as the No. 2 recruit in the nation in the Class of 2006 by Soccer Buzz magazine and was named to the Parade Magazine All-America team in 2005.
Heath committed to attend the University of North Carolina (UNC) when she was due to begin her junior year at high school. She did not play soccer in her senior year, instead she decided to train with boys. In her consensus freshman year in 2006 with the Tar Heels, she was part of the All-America 2006 national championship team and made 23 appearances at left midfield (22 of them were starts), scoring four goals and assisting nine. As a sophomore, she scored two goals, assisting another five, and was named to the First-Team NSCAA All-American and First-Team All-ACC (Atlantic Coast Conference). As a junior, she scored eight goals with eight assists, this helped the UNC to a 25–1–2 record and the NCAA title.
Heath helped lead UNC to NCAA Division I Women's Soccer Championship titles in 2006, 2008 and 2009 and four straight Atlantic Coast Conference titles. UNC soccer coach Anson Dorrance notes that Heath preferred to nutmeg opposing players rather than dribble the ball around them.
Heath played on several youth national teams – including the U-16s in 2003–2004 and the U-17s in 2004–05. Heath was a standout at the 2006 FIFA U-20 Women's World Championship in Russia, despite being of the last players chosen for the World Cup roster. In total Heath made 24 appearances for the USA Women's U-20 National TeamU-20s in 2006, scoring five goals. Heath was part of the silver medal-winning USA Women's team at the 2007 Pan American Games in Brazil where she was in the starting lineup for the championship game.