Nikolai Ognev's book "The Diary of Kostya Ryabtsev" was published in 1927. "Diary" is written in a peculiar language, typical of school vernacular jargon with mischievous words and dashing sayings of Kostya himself and his comrades. The 15-year-old hero frankly writes about the difficulties and experiences associated with the years of puberty. Kostya Ryabtsev is not an easy student. Just expect trouble from him... And he is rude and does not always study well.