They include Charms, Defence Against the Dark Arts, Potions, Herbology, Divination, Astronomy and Care of Magical Creatures.
JK Rowling's Pottermore website says it "will take you back in time" to learn about the "traditional folklore and magic" that is at the at the heart of every Harry Potter book.
"In addition to exploring the origins of magic through history and folklore, the eBook shorts will also feature notes, manuscript pages and charming sketches as previously seen in Harry Potter: A History of Magic."
The first two books, Harry Potter: A Journey Through Charms and Defence Against the Dark Arts and Harry Potter: A Journey Through Potions and Herbology will be released on June 27.
The third and fourth books - Harry Potter: A Journey Through Divination and Astronomy and Harry Potter: A Journey Through Care of Magical Creatures - will be released soon after.