The Ausbausystem 1 S was the Schülerübungssysteme version of the Ausbausystem 1 (8100) model and added the an A4 format version of the 1101 model’s Elektrik II Lehr-und Lernkartei (teaching and learning cards) documentation. The A 4 format Elektrik II documentation was published in German, French, Italian, and English. The Elektrik II documentation in an A 5 format was not published.
The Braun era proof photo shows the light bulb, thermister and photo cell blocks. During the LectronMW era, these three blocks would be transitioned to the Grundsystem S model.
I can confirm this because I was able to acquire a previously never opened Ausbausystem 1 S model which included a 1971 catalog and its layout matched the above layout photo exactly. Unfortunately, Braun does not appeared to have put a photo of the Grundsystem S or Ausbausystem 1 S models in any published document.
The opened box layout.
During the LectronMW era, a different plastic tray was used and the layout reflected the transition of the three mentioned blocks accordingly. One banana jack block was also eliminated.