Not all senior discounts require you to be over 65.
Check with local stores to see what their policy is and check Senior Discounts Web Site for discounts in your area. Also look out for Senior Discount Cards which are available at some locations.
Kroger offers a discount to seniors over 60 on certain days of the week (check with your local store).
Ross Stores offer a 10% discount on Tuesdays if you are 55+.
International House of Pancakes and Dennys has a separate menu for those 55 and older.
More restaurant discounts here
AARP members also receive discounts to various restaurants and services with an annual subscription.