A native of Milwaukee, Wisconsin,[2] Chojnacki graduated from the city's Marquette University High School in 1958.
[2] During the 1970s, he was among the staff of American Greetings, a card company based in Cleveland, Ohio;[5] he licensed the Holly Hobbie character early in his tenure there.
[6] Later that decade, he set up the company's licensing branch[5] Those Characters from Cleveland[7][8] with another AGC employee, Tim Wilson (the creator of the comic strip Ziggy).
[5] Beginning in the early 1980s, Chojnacki served as co-president of Those Characters from Cleveland[8] along with Wilson,[10] and vice-president of AGC's licensing operations.
[12] He served as executive producer of 1985's The Care Bears Movie,[13][14] along with its 1986 prequel A New Generation;[15] he also was a creative consultant for the 1987 follow-up, Adventure in Wonderland.