Children's books are permeating entertainment, TV, movies, etc. Emily thinks Stephen Colbert said it best.
"A young adult novel is a regular novel that people actually read."
Most book buyers actively discover books by asking friends, browsing in bookstores, and reading reviews online. This is the seed of what the marketing team does; they take word-of-mouth and build it.
Building support with booksellers is key.
Penguin still prints catalogs, they create F&Gs/ARCs, as well as create a catalog of their backlog. They do trade advertising, as well as special mailings.
Penguin attends Book Expo America (BEA), which give them a chance to put their best foot forward. "We represent our books and get support." Face-to-face opportunities where they as the publisher get to represent their books.
On getting their books notice: People have to find your book. Penguin works with their sales reps and get promotions (displays, posters, etc.) so that the book is noticed.
The teacher and librarian market is powerful because it gets books in the hands of readers. Penguin is sure to get their books on state list. They also attend conferences that teachers and librarians attend (like ALA), as well as provide teachers with material they need to use their books in the classroom.
Reaching consumers is now heavily done through social and digital means. They've invested in all the platforms to be certain they have a reach and build the many communities who might buy their books.
Advertising is done through print, digital/search, broadcast.
Sale. Marketing. Publicity. They all work together.