 Other early retaining walls were erected in the school grounds before 1940, such as those adjacent to the tennis court.By 1936 trees were planted to the west of the tennis court and along the southwest boundary of the school grounds, facing James and Heal Streets.The Great Depression, commencing in 1929 and extending well into the 1930s, caused a dramatic reduction of building work in Queensland and brought private building work to a standstill.