MOSES LAKE — It sounds like the start of a very bad joke.

“Wanna race a rubber duck?”

But that’s exactly what’s going to happen at Cascade Park from 11 a.m. to 2 p.m. Saturday as people gather from hither and yon to put rubber ducks in Moses Lake and see which ones come in first.

It’s all for a very good cause, to support the Boys and Girls Club of Moses Lake.

“We are doing a family fun day on Saturday,” said Rachelle Lange, director of resource development for the Boys and Girls Club. “It will all be very kid friendly.”

The duck race itself will start at 1 p.m., and will involve tossing 4,000 to 5,000 rubber ducks in Moses Lake, funneling them along and through a special course, and seeing which one comes in first.

Lange said there are still opportunities to enter the race by purchasing or “adopting” a duck.

“One duck is $5, five are $25, and 25 ducks are $100,” she said. “There are multiple chances to win.”

Lange said first prize — the winning rubber duck — wins its sponsor $1,500. Second prize is $1,000, third prize is four tickets to a Seattle Mariners game (plus a parking pass), fourth prize is $250, and fifth prize is $100. There will be a number of other prizes too, such as coffee prizes and Dominos Pizza coupons, Lange added.

“You don’t need to be present to win, but we would love everyone to be there,” Lange added.

This is the sixth year that the Boys and Girls Club have sponsored the Duck Derby in Moses Lake, Lange said, and it is the club’s biggest fund raiser of the year.

“It keeps our doors open, keeps the kids happy, and continues to develop our community,” she said.