Macdonald trained at the South Kensington Schools where, in the end, he became an assistant in the studio of the Painting Master Robert Collinson.
"[1] From its inaugural year 1865 until 1871, Macdonald was Master (principal) of the Oxford School of Art housed in the future Ashmolean Museum.
[2][3] When John Ruskin became Slade Professor at the University of Oxford, he was critical of the teaching methods at the school and in 1871 founded the Ruskin School of Drawing, retaining Macdonald as master.
[2][5] Ruskin had, through pressure from the backers of his new school, reluctantly accepted Macdonald, who as Master of the Oxford School of Art taught to the South Kensington system which Ruskin despised,[6] and when as Ruskin Master didn't adhere to Ruskin-ian principles of copying from "stone, leaves and flowers" rather than directly from the life model or En plein air.
[6] While at the Ruskin School of Drawing Macdonald taught part-time at Radley College and took in private students, this to supplement his salary which was, for twenty years, provided by Ruskin.