McGraw-Hill Education produces the answer keys for Math with Pizzazz books. There are two Math with Pizzazz series, Middle school Math with Pizzazz! and Elementary Math with Pizzazz!, and the answer keys to both series are available for purchase under the "Teacher Materials" menu on the McGraw-Hill Education website.
Some of the materials for the Math with Pizzazz series are only available to educators, but they can purchase the answer keys through the McGraw-Hill Education website with an existing account. It is also possible to create a new account for registered users of MHschool.com or Glencoe.com with the same email address used for accounts on those sites, allowing teachers to receive a discount on these classroom materials.