Power of Attorney for HMH Holding Inc. Director

This filing contains a Power of Attorney granted by M. Georgia Magno, a director of HMH Holding Inc., to Thomas W. McGee, Dwight W. Rettig, and Cindy Nichols. The attorneys-in-fact are authorized to execute and file necessary SEC forms, including Forms 3, 4, and 5, on behalf of M. Georgia Magno. This authorization covers electronic filings, amendments, and any other actions deemed necessary for transactions involving the company's securities. The Power of Attorney remains effective until M. Georgia Magno is no longer required to file such forms, revokes it in writing, or the appointed attorneys-in-fact are no longer affiliated with the company. The filing also includes a notary acknowledgment dated April 21, 2025.