"Rote Reihe" was a series of music education books published by Universal Edition from Vienna. Approx. 80 books were published in this series in the 70s and 80s, many with scores and exercices on experimental music for children. Some of the books came with 7" records. Here's side B from Nils Hansen's "Kreativität im Musikunterricht" (creativity in the music class), played by 5th graders (track 1) and 12th graders (tracks 2 and 3).