What’s the deal with the ALS ice bucket challenge?

Scores of people are filming themselves dumping buckets of ice on their heads, posting the video to Facebook or Twitter, then challenging their friends to do so, too. The chilly action is intended to raise awareness of ALS, or Lou Gehrig’s disease.

Over the weekend, even 86-year-old Ethel Kennedy, widow of Robert F. Kennedy, got in on the action, challenging President Obama from her Hyannis Port, Massachusetts compound. He is set to vacation on the island this week. “Welcome to Cape Cod, Mr. President. I nominate you,” she said, after dousing herself with 19 family members.

So far, the campaign has raised $168,000, a jump in the $14,000 raised during the same 10-day period last year, according to ALS Association estimates. Started by Boston College baseball player Pete Frates several months ago, the movement has gone viral with the hashtag #icebucketchallenge or #StrikeoutALS. Frates was diagnosed in 2012, and has since become paralyzed, only able to eat through a tube.

“It just proves the goodness of human beings and the power of people. The power of positivity,” John Frates, Pete’s dad, told ABC Boston. “All we needed, really, was a bucket and a bag of ice to create all the awareness we ever needed.”

Matt Lauer of NBC’s Today Show helped propel the movement in mid-July when he was the recipient of an ice bucket himself on-air, and then challenged Martha Stewart, who accepted.