Mr Pickard, who was previously features editor of The Scotsman, is the longest-serving editor of any News International paper. He is only the second editor of the TESS since it became a separate edition of the Times Educational Supplement in 1965.
James MacManus, chief executive officer of TSL Edcation, the parent company of Times Supplements, said this week: "When Willis took the job, the TESS was often selling fewer than 4,000 copies north of the border.
"He has greatly expanded its coverage of primary, secondary and further education and will leave a title selling almost 9,000 copies weekly as a result.
"It is an achievement that has benefited both the paper and the community it serves."