After attending the local school in Bridgewater, Jackson went up to Harvard in 1904 at the age of 16 to study mathematics, graduating A.B in 1908 and A.M. in 1909. He then moved to continue his studies at Göttingen for two years with the help of Harvard Fellowships. He returned to Harvard in 1911 as an instructor in mathematics and was promoted Assistant Professor in 1916. During the First World War he became an officer in the Ordnance Department where he produced a booklet of range tables for the artillery. In 1919 he took up a professorship in mathematics at the University of Minnesota, remaining there until his death.[3]