Gender: boy
School:
School #20A
A search for Z* Sliwinski turned up two results--Zalme and Zelman. They were both born in the same year and lived at (almost) the same address, so I concluded they were the same boy. In addition, the birth year makes Zalme/Zelman the right age to attend School #20A.
No other person with the last name Sliwinski had an address to match Zalme/Zelman's.
He was deported on September 9, 1942, on which date there was a deportation to Chelmno.