In December of that year, he founded the 1st Kamionkowska Scouting Chapter in Grochów, which was joined by a platoon from 32 WDH, under the command of Janek Makowski.
From the start of the occupation, Skorupka was the "spiritual leader", so to say, of the "Cospiratory Scouts" (konspiracyjne harcerstwo), the Szare Szeregi (Grey Ranks) from Praga.
Skorupka then became completely absorbed with the resistance work, and he became the communications liaison to the commander of the "Home Army’s" Praga division.
When asked by Stanisław "Orsza" Broniewski (successor of Naczelnik Szarych Szeregów) about how many Scouts there were in Praga, Skorupka replied that there were 3,000.
When asked on what basis he arrived at that figure, he replied: "All I have to do is whistle and 3,000 boys will assemble themselves on the corner of Targowa and Zamoyskiego St. That is how many were in the Praga Chapter on 1 September 1939, nothing has changed here!".
In August 1944 Kazimierz Skorupka posthumously received a second "Cross of Bravery" (Krzyż Walecznych), being promoted to "Second Lieutenant".