Physicists have determined that the best way to subdue wall-bouncing photons is to let them loose until they need a nap. Apply the latest scientific findings to your kid’s playtime with today’s Groupon at Safari Adventure in Riverhead. Choose between two options:

• For $18, you get three open-play admissions for a child 3 years old or older (a $36 value).
• For $12, you get three open-play admissions for a child younger than 3 years old (a $24 value).

Safari Adventure is home to an 11,000-square-foot jungle playland, where intrepid tykes can scale the four-level Kilimanjaro playground complete with tubes, slides, obstacles, and cargo nets. Enormous inflatable bouncers introduce little ones to the wonders of gravity defiance, and more than 40 video and skill games push their dexterous digits toward thumbs-up glory (tokens not included in today's Groupon). Pre- and postexploration, starving safarians can also munch on healthy snacks—whole fruit, yogurt, salads, and more—at the Lion's Den Café.