Get 15% off your check when you show your AARP card at Denny's.  The discount is good for your entire check, but some restrictions apply.  The AARP membership is available to anyone aged 50 and up.  The AARP discount is not good with other coupons or offers.  To receive your 15% discount, just show your valid AARP membership card any day of the week.  Denny's and AARP announced the deal on the AARP Discount site.