Hi Peter,
I'm a Cinderford lad and grew up near the "old" EDGS site in the 60s, it was off Station Street/College Road. Everyday mum listened to Radio 2 so I "grewup" with JY. He was a real favourite, perhaps as he had used to work for her baker (Kears?) some years earlier, but mainly as he gained interviews with the hard-to-get: PMs, Royalty and Sir Denis Healey who's wife Edna May Edmunds came from Cinderford and attended Bells GS in Coleford.
(I have a passion for the Forest & 50s pop music so heartily recommend JY's autobiography).

In the late 40s my mum attended EDGS. She recalls hating the long walk up to the playing fields on the top of St Whites Hill, in all weather, for PE on a windy sloping field. They were only allowed a few minutes for this long hike. Not good if a late afternoon lesson as she HAD to catch the bus home to Longhope...

In the 70s I attended the new Grammar School at Five Acres Coleford, some of my teachers had taught my mother !. I then joined Ranks as an apprentice in 78. The RX Training School was on the site's edge in the beautiful Dean sandstone "Maltings", once Wintle's Victorian Brewery. This is still there renamed "Mews" & visible from the village centre just off the High Street if you want to visit.
http://www.geograph.org.uk/photo/1663778
(Thankfully the monstrous external lift and fire escape wern't there in my day !)

This was the same building which BAF moved into to avoid the London bombing, they produced searchlight equipment, gunfire direction tables and later film projectors (Rank Aldis). When I was there and your father before me it was odd, the stairs were very steep (no lift), the ceilings low, and the long floors had shallow gradients down to the central stairwell to apparently assist the brewing processes; this all took some getting used-to, especially while wearing our heavy steelcapped workshoes & having to stand to work all day!. This old building eventually grew into the 60 acre RX plant of several hightech buildings and over 4000 staff by 1982, with precision optics still being the key to their photocopier products. The RX site is now the Vantage Point Business Village; the sprawling site was deliberately planned with several buildings separated by proper access roads, car parks, two H&W Boiler Houses etc so it could be divided into a business/industrial park if(when?) the Xerox business fell into decline. This TV news film gives an impression of the site.
http://www.youtube.com/watch?v=Hj17VLRUQCc
Plenty of early and more recent photos of the BAF/RX site here, eg
http://www.sungreen.co.uk//Mitcheldean-Dean-Glos/rank_xerox_from_air.html

RX sent me to day-release at "EDGS" to start my engineering qualifications, albeit by then called the West Glos College of Further Education. Locally it was called "the Tech"; it had grown from the "Mining & Technical College" which had adjoined the School since the 20s. By now my mum was back to teach Cookery. I recall the original part of the College was a beautiful well-built single storey building, a long tiled central corridor with old statues/plaques (?) and attractive hardwood fittings and stone carvings as befits a grand old school. By coincidence our nextdoor neighbour Sid Wilce was the caretaker, I think he saw it as a draughty,leaky, old place !
http://www.forest-and-wye-today.co.uk/news.cfm?id=47417
http://www.sungreen.co.uk/EDGS/EDGS_Buildings_1980.html
Several photos c1975 starting here, use the green arrows to scroll thro them
http://way-mark.co.uk/foresthaven/livnhist/slide082.htm#

Ranks then sent me in 1981 to the Polytechnic Of Wales in the Rhondda (itself originally the Treforest Mining College). On my course I met a young student and still good friend fresh from the Yorkshire coalfields. 30 years later he is now based in Telford and amongst many sites around the UK is responsible for the Vantage Point site's building services (heating, aircon, etc), which I worked on as an apprentice in 1981/82 before we'd even qualified !

The aforementioned Photos website has many pictures of both Schools, buildings & people, including many official School Pupil Photos from the years when your father was there. I believe JY left school aged 15 so about 1936, prior to delivering bread until his parents divorced and he moved to S. Wales. (his birthdate is supposedly 1923 but even his book says 1921 as he lied abt his age to join the RAF early when WW2 started).
However and rather oddly, from FreeBMD;

Surname Given Name Mother District Volume Page Transcriber
Births Dec 1921
Young Leslie R. Woolford Westbury S. 6a 493 PLabott

Anyhow and more importantly, if you study the 1933 & maybe 1937 Photos hopefully you'll find your father. Sadly as yet no-one's tagged names to these particular photos. The Friends Reunited site also has many photos etc.
http://www.friendsreunited.co.uk/School.page/East_Dean_Grammar_School/7989/Details

Re EDGS, if you want more information re their very interesting history, I strongly recommend the special copy of the "Oak Leaves" Magazine the Old Scholars Assocation produced for their Centenary in 2010. Thro' this I was amazed yet delighted to learn that my favourite RFDGS teacher Mr Fern, a patient, firm but friendly elderly gentleman, had been a WW2 RAF Squadron Leader DFM.
http://www.forum.forest-of-dean.net/index.php?id=27516

The front buildings facing Staton Street are still there as Dean House, Glos Council offices, I visited last year to have a peek. Sadly the attractive wall mouldings etc which were just inside the main entrance are either covered by plasterboard or, perhaps more likely, went i to the skip, as new partitioned-offices are there now. Most of the rest of the old site at the far end has now been built over for housing, appropriately called Colliers Field.

I hope some of this has been of interest.

Searching the internet re the history of BAF has been harder than I anticipated. This is presumably partly because the prewar British film industry initially comprised a huge number of small firms within an ever-changing business of takeovers and merges, especially after the onset of "talkies" ie sound. British Acoustic Ltd was the major Sound element of the The Gaumont British Picture Corporation Limited, the UK's largest film company.
http://www.nigelo.plus.com/gaumont/index.html

I suspect as with many high-tech industries the combined national War effort relied heavily on the film industry and associated industries, this would have caused even faster changes of technology and company location, organisation & ownership.

As their name suggests British Acoustic Films were particularly noted for the sound technology, hence your father's involvement.

This helps relate BAF and Rank:

"Rank Precision Industries Division

Gaumont British had among its subsidiaries British Acoustic Films Ltd, which manufactured sound equipment for cinemas and also manufactured and marketed 8mm and 16mm projectors and cameras under arrangements with the Bell & Howell Company, a major American manufacturer of such goods. Taylor, Taylor & Hobson Ltd, a subsidiary of British Acoustic Films Ltd, was an internationally known company manufacturing precision measuring instruments and special-ised lenses. A further subsidiary of Gaumont British was Cinema-Television Ltd, trading as Cintel, engaged in the development and manufacture of electronic equipment, cathode-ray tubes and cinema largescreen television. Yet another subsidiary of Gaumont British was G.B-Kalee Ltd which among other activities marketed general cinema supplies. In 1947 British Optical & Precision Engineers Ltd was formed as a public company, and was subsequently re-named Rank Precision Industries Ltd. It acquired the businesses of British Acoustic Films Ltd and G.B-Kalee Ltd and at the same tune acquired the rest of the share capital of Taylor, Taylor & Hobson Ltd (i.e. that portion not already held by British Acoustic Films Ltd). At the same time it acquired control of the business of A. Kershaw & Sons Ltd (manufacturers of cinema projectors) and also became responsible for manufacturing and marketing internationally (excluding the American continent) a part of Bell & Howell's range of cameras and projectors."
http://www.competition-commission.org.uk/rep_pub/reports/1960_1969/fulltext/054c02.pdf

Also see this excellent site, always good if trying to trace old British company histories and brand names etc.
https://www.gracesguide.co.uk/British_Acoustic_Films