Henderson was one of the top running backs in the class of 2025.
The Nittany Lions added six new forwards, three defensemen, and two goalies in the latest round of player signings.
The captain became the fifth Penn state men's hockey player to enter the portal.
Gaines committed to Penn State in 2023 before decommitting in March.
The announcement came after Parker decommitted freom West Virginia on Monday.
This was McClain's second time entering the portal after transferring to Penn State last year.