Praeger completed her high school education at Brisbane Girls Grammar School. After graduating high school, Praeger went to the government vocational guidance section to inquire about how she could further study mathematics. The vocational guidance officer she spoke with tried to discourage her from studying mathematics further, suggesting she become a teacher or a nurse because two other girls who came to him wanting to study maths weren't able to pass their courses. He reluctantly showed her an engineering course description, but she felt it didn't have enough mathematics. So she left without getting much information that day, but did continue on to receive her bachelor's and master's degrees from the University of Queensland.