You can purchase a "Luxor Pass" valid for 5 days from an office near Luxor Museum or from Luxor Public Library: ask at reception for details. You will need a passport-photo and a photocopy of your main passport page.
Details of this pass, and of entrance ticket prices to many sites and museums in Egypt are available here.
The West Bank at Luxor is probably the largest open-air museum in the world! To enjoy it best, if you are planning to visit several sites or museums, you should check up on the ISIC, ITIC and IYTC cards. They offer a discount of about 50% on most entrance fees, as well as discounts on railway tickets. For a small annual fee students, teachers and young travellers get the discounts at any ticket-office. Get the cards before you travel. The ISIC card is also available from the office of Egyptian Student Travel Services, haled Ibn Al-Walid, Al-Awamiya Island, Luxor. You will need 2 passport-photos, photocopies of your main passport page and of your valid student or teacher card, or proof of age for the Young Person's Card.