Complex sentence: For many years the company continued its focus on serving the youth market, publishing low-cost magazines and later paperback books, The company continued under the name Scholastic Magazines throughout the 1970s.
Split into simpler sentences: For many years the company continued its focus on serving the youth market, publishing low-cost magazines. Even with the later transition into paperback books, the company continued under the name Scholastic Magazines throughout the 1970s.