IRVINE – First-grader Kenneth Shinozuka thought of a problem: Because people are living longer, more of them are falling down in the bathroom. "But they do not want to be monitored by video cameras for privacy."

Then he thought of a solution: bathroom floors with sensors that send information to a wristwatch worn by an elderly person's "daughter."

The watch notifies the daughter not only when "grandma" enters the bathroom but what she weighs at that moment.

If "grandma" falls down, the boy writes, the watch will beep, alerting the daughter to come quickly.

Smart Bathroom was one of nearly 300 inventions on display Saturday at Irvine Valley College. The annual Astounding Inventions contest challenges kids in the Tustin and Irvine school districts to unleash their imaginations.

"Tonight Show" scouts scoured the bustling gymnasium for precocious child guests. They weren't disappointed. Many of the inventions solved problems that have been plaguing kids for years.

Take Kareem Khaled's Double-Sided TV, invented to prevent sibling blowouts. "I want to watch TV in peace," the student wrote.

Shweta Mehra invented the Sprinkling Alarm to spray water on kids who oversleep. "You'll be awake ina few seconds," she writes in her inventor log. "Not only that, you will also be extremely fresh."

There was the Bouncy Pencil, wrapped in rubber so that when you drop it (which you inevitably will), it bounces right back to you. The double- headed toothbrush so you can clean upper and lower teeth at the same time. And toilet paper with dotted lines to show potty-trainees how much to tear off.

Other inventors attempted to get a bit more scientific. Take Brandon Ferguson and his Lunar Colonization. Under "problem solved?" in his inventor log, Ferguson wrote: "Colonize the moon safely." When the inventor log asked "How?" He wrote: "Construction droids will do the job."

In the "awww" category was first-grader Samantha Mickelson, who invented the Talking Lunchbox to give day-care kids "a chance to hear their mom's or dad's voice" (recorded on a microchip in the lid) when they snack.

And first-grader Nolan Foreman had judges gulping with his Tear Catcher. The boy glued sponges to the bottom of sunglasses so that his face wouldn't get wet when he cried.

Christopher Paplham was inspired by a doll that talks when spoken to. The second- grader asked his dad if he could take apart the doll and use the voice. "He gave me a weird look and said yes," the boy wrote in his inventor log. The boy wrote that the doll voice chip could be used to record positive messages from teachers, parents, "even yourself!" and then inserted in your notebook to play when needed.

Fifth-grader Daniel Kim also mentions his father in his inventor log. His dad absent-mindedly put up the car windows one day, crushing the boy's fingers – and inspiring a power window sensor called Crushed Fingers Nomore.

In the end, everyone with an invention got a ribbon, and some got $25 or $50. The point is not winning, said Irvine Valley College spokesman Mark Goddard, but "creativity, imagination and the application of it."