Jack will work closely with the club's Academy director, Steve Harper, and management team to provide support to the Academy's coaching structure and players in the Under-9 to Under-16 age groups.
Steve Harper said: "Jack is a very experienced manager, coach and coach educator. His knowledge and experience will be of huge benefit to us during his time here."
Jack's arrival follows Neil Winskill's deployment to a coaching role with the Magpies' Under-21 side.
Born in Falkirk, Jack made more than 300 league appearances as a player in Scotland, as well as spending time at Hartlepool United.
As a coach, he has overseen almost 300 senior games at clubs including Alloa Athletic, St Mirren, Sunderland, Hibernian and Dundee United.