 Complete the following phrase:  Stefanidi attended the 1st High School of Pallini and won the National High School Championships. She broke the National High School record and the Championship record winning gold at the 2006 Gymnasiade. Growing up she broke all of the World age-group records for the ages of 1114 and right after she turned 15, she broke the World Youth under-18 record with a jump of 4.37 m. Her first international experience came at the age of 15, when she represented Greece at the 2005 World Youth Championships in Marrakesh, placing first with 4.30 m. At the 