When Sarah Mitchell waved her daughter off on her first day of kindergarten, she had no idea that two months later she would be responsible not only for Annabelle's education, but also that of 1.2 million other NSW school students.

Ms Mitchell, a National Party MP, was one of the big winners in Gladys Berejiklian's cabinet reshuffle this week, jumping from the junior portfolio of early childhood education to one of the most significant ministries in the state.

Wednesday was her first official day as Education Minister. "It's a big step up for me, but I think it's one I can do well," said Mitchell, a graduate of Gunnedah South Public School, Gunnedah High and the University of New South Wales.

New Education Minister Sarah Mitchell with her daughters Matilda (1), and Annabelle (5). Credit:Nick Moir

"It's an area I am really passionate about. I think education is the key to anybody having success in life, and to be able to be in a position to help change and shape that is pretty exciting, especially with my background and my age."