Bonjour Monsieur GAUDIN, Comment allez vous!
I am replying to your recent posting regarding DEBREUCQ, MAURICE EMILE VICTOR, born 6th March 1894 in Solesmes (North of France) who signed on to the Titanic on 6th April 1912 as assistant waiter for A LA CARTE RESTAURANT STAFF who was employed and paid by Mr. LUIGI GATTI who formerly worked at Oddenino's Restaurant in London. You asked: "Where can I find information about this Restaurant?"
I commend you for wanting your students to learn about Important Events, and especially personalizing the exercise by tracing a local resident who was impacted by the event. I have been tracing A W BARRINGER, a first class steward on the Victuallizing staff who was my grandmother's elder brother, and this makes the Titanic tragedy "alive" to me.
As to local resources, I would suggest starting with the Titanic Societies (there are several in the US, UK, and elsewhere), all with websites. Also with the libraries in Southampton.
http://www.southampton.gov.uk/ has several search pages that may lead to references to check out.
Goggling for ""Oddenino's"&"Restaurant"&London" yielded 114 web pages, most referring to bands that entertained the patrons. (Likely, Oddenino's was a fashionable restaurant or "night club" where Londoner's entertained in the 1920s-1940s and possibly into the 1950s.)
The two Oddenino's references on webpage
http://www.mgthomas.co.uk/DanceBands/IndexPages/LondonDancePlaces.htm
suggest that it was located near "Piccadilly Circus" or at "54-62 Regent Street" (others more familiar with London can confirm this). There may be books that also describe famous restaurants in London, or possibly another message board or mailing list that covers London whose members may be more knowledeable, that could provide more details if you want to learn more about the original restaurant where he worked.
http://www.1st-hotels-kensington.co.uk/
and several other webpages list
"Royal Garden Hotel (Oddenino'S) Ltd
2 Kensington High Street, Kensington, London, W8 4PT" though viewing the "Royal Garden Hotel" website does not list any current restaurants named "Oddenino's"; neither is the location of this modern hotel anywhere near "Piccadilly Circus" or "Regent Street", so probably unrelated.
As to the address where MAURICE DEBREUCQ lived in London: "12 Mead Street, KENSINGTON,LONDON, W" and its relationship to "Piccadilly Circus" or "Regent Street" or "Kensington High Street" (where the hotel is now located), only a Londoner (or a good map) can illustrate.
http://www.maxpages.com/europe/London has links to modern maps of London
Mr LUIGI GATTI's sign-on listing said he lived in a house named "Montalgo", Harborough Road, Polygon, SOUTHAMPTON.
Someone in Southampton (possibly Brian) may be able to photograph the house if it still stands.
http://contueor.com/baedeker/great_britain/southampton.htm
This map shows the location of "Polygon" neighborhood though I could not spot "Harborough Road" on this map.
http://www.maxpages.com/europe/Southampton is a page with links to more modern maps, though some links are obsolete.
You have probably discovered this prior posting by Brian Ticehurst regarding Luigi Gatti.
www.encyclopedia-titanica.org/item/4770
I realize I may not have provided the information you wanted, as I live in the US. With the help of members of this excellent website, I hope that your search proves fruitful.
