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: for $18, you get six one-hour Open Jump admissions at Jump-N-Party (a $36 value). Hosting kids’ exercise and entertainment within massive multicolor plastic cathedrals, Jump-N-Party’s facilities accommodate children up to age 12. High jumpers challenge friends to a race down an 18-foot slide, craft a cocoon in an obstacle course, or combine their strengths for the mythical triple bounce. Spread your Groupon over six months with hourly family-night visits or spend six straight hours one wintry morning leaping, stumbling, and making merriment across an inflatable indoor labyrinth. Open Jump occurs the first Monday evening of the month from 3 p.m. to 7 p.m. and every Tuesday through Friday from 10 a.m. to 2 p.m.