http://www.nps.gov/findapark/feefreeparks.htm -you can get free entry into any of the National Parks on these days in 2019: January 21, April 20, August 25, September 28, and November 11.
https://www.bestbuy.com/site/video-games/best-buy-gaming-events -on Saturday, September 21 from 11AM to 2PM, participating Best Buy stores will have a Free Pokémon Trade and Play Day Event. While supplies last, participants will receive a booster pack that consists of a three-card mini pack, activity sheet, Pokémon coin and guide.
https://www.moes.com/free-queso-day “Stop by your local Moe’s on Thursday, September 19 for a free 6 oz. cup of our famous Moe’s queso! No purchase necessary.” –locator
https://www.facebook.com/LongJohnSilvers/photos/a.20514379 -on Thursday, September 19 talk like a pirate at Long John Silver’s Restaurants to get a Free Piece of Fish. . Dress like a pirate to get a Free 2 pc Fish Basket. –locator
https://www.gamestop.com/20190928_LegoEvent.html? -Build and take home a mini LEGO Overwatch Ganymede at Select GameStop Stores on September 28 from 2-4PM. Enter your zip code on that page to find a participating store near you.
http://www.thefreeosk.com/find-a-freeosk/ -use the locator on that page to see if your Walmart is participating. If they are, visit the Freeosk Sample Booth at your store to get Free Tabasco Samples. Participating Sam’s Club stores will have Free Downy Unstopables Samples.
https://www.hallmark.com/stores/? -Hallmark Gold Crown members(register here) can visit Hallmark Gold Crown stores every Friday between now and September 27 and get a Free “Just Because” Card. –locator
https://www.smithsonianmag.com/museumday/museum-day-2019/ -get Free Museum entrance on Saturday, September 21 2019 from Smithsonian Magazine. You can find Participating Museums at this link, and tickets will be available on August 15.
–Update – Tickets are now available.
https://www.walmart.com/cp/6114757? – on Saturday, July 27 from 10AM to 4:30PM Walmart will have a Free Steam Day of Play Event for kids with fun STEAM activities, including how to tie dye, create slime, & make a cereal necklace. Enter your zip code on that page to find a participating store near you.