In Jardine's time, preparing the pupils for war was also important.[5] According to Jardine's biographer, Christopher Douglas, the pupils were "taught to be honest, impervious to physical pain, uncomplaining and civilised."[6] All pupils were required to be academically competent and Jardine was able to get along without exhibiting brilliance; successful sportsmen, on the other hand, were revered.[7] Jardine enjoyed a slightly better position than some pupils, already possessing a reputation as a cricketer and excelling at other sports; he represented the school at football as a goalkeeper and rackets, and played Winchester College football.[8] But it was at cricket that he excelled. He was in the first eleven for three years from 1917 and received coaching from Harry Altham, Rockley Wilson and Schofield Haigh, the latter two of whom were distinguished cricketers.[9] In 1919, his final year, Jardine came top of the school batting averages with 997 runs at an average of 66.46. He also became captain despite some doubts within the school about his ability to unify the team.[10] Under Jardine, Winchester won their annual match against Eton College in 1919, a fixture in which Eton usually held the upper hand.[11] Jardine's batting (35 and 89 in the match) and captaincy were key factors in his side's first victory over Eton for 12 years.