Wolves are kids in second grade (or 8 years old). This part of the Boy Scout trail is intended to take one school year, preparing the scout to begin earning his Bear rank after he completes second grade.
Much of the advancement for the Wolf rank is done by the scout with his family outside of the den. The parent signs off in the scout’s handbook and the Den Leader records the advancements from the handbook. As the Tiger program was completely family oriented, so the Wolf program relies heavily on family involvement. You will see this gradually change with the scout doing more with his den and more individual direction as he reaches Webelos.