Mrs. Czerwicki is the detention monitor at P.S. 38. She is seen in all of the books except for "Big Nate Lives It Up."
Mrs. Czerwicki has a white, curly, frizzy wig, which she wears all the time, leaving her real hair a mystery. She is usually seen wearing a sweater.
Czerwicki is devoted and easily interested, something she hides under a sarcastic, laid back persona. Still, she is surprisingly lenient for one in her position, allowing Nate to speak up and giving him honest answers, and even considering tolerating his venture to the art studio.
She is fond of reading romance novels during detention to pass the time, possibly because her romance with Mr. Czerwicki is a huge strain. Nate sometimes uses this to escape detention. He waits for her to get into a very engaging chapter, then asks to leave.
It is unknown how Czerwicki became detention monitor. Her husband took her to a hockey game for their anniversary, making her angry. They had two children, though Czerwicki seemed estranged from them. Eventually, her son was imprisoned for reasons unknown.
Shortly after her wig caught on fire, she told Nate he had broken the record of the most detention slips. This made him very excited, as he had been attempting to surpass everyone else throughout the day.
At some point prior to P.S. 38's passage to Jefferson Middle School, she told Nate that he received three detentions that week. She also gave Nate the idea for the P.S. 38 Cartooning Club.
On two occasions, she is shocked that Nate got ten detentions, which is a new record.
Mrs. Czerwicki has a strained relationship with her husband. This can be proven, as he gave her Madden NFL 25 for Christmas (which she apparently did not appreciate), watched the History Channel during Valentine's Day and forgot all about the holiday, brought her to hockey game during their anniversary, and many more.
Mrs. Czerwicki once compared Nate to her son, as Nate is always in detention, and her son is in prison. Mrs. Czerwicki seems to be estranged from her daughter, since she met her boyfriend from the internet, which Mrs. Czerwicki does not appreciate.