Go here and click Shop Now to get to Walgreens website. You will see photo on the homepage, click that. Then click the picture that looks like the one below:
Once there, decide if you want 25 prints free or a desktop calendar free. (Tough choices, I know!) Enter FREE4X6 for the prints and FREEFORU for the calendar.
NOTE: The calendars are NOT available for free in-store pickup. Shipping starts at around $6.