I wasn't aware of this one before, but I'm told some volumes where in the Geneva Books catalogue last week, though sadly they were gone before we had a chance to get them.

CBA have listed;

KNOWING THE SCRIPTURES: Knowing the Scriptures: a magazine with an appeal to Christian youth. (Glasgow, Elim Hall Bible Class,) 1939,1941-47,1951-57.

Also, 

In "The Believer's Magazine", New Series 40 (1939) there is a note on page 24: "GLASGOW.—The Fifth Annual Conference, exclusively for Christian Youth, under the auspices of the magazine 'Knowing the Scriptures,' will be held on Saturday, 28th January, at 3 p.m., in St. Mungo Halls (seating 1400), Moffat Street, Glasgow, C.5. Speakers, C. J. Tilsley, India; E. T. Tarrant, Folkestone; Jas. Moffat, Glasgow."