. >> i'm peyton robertson. >> reporter: peyton robertson has the enthusiasm of an infomercial king. is in his audition tape for this year's young scientist contest. with the ingenuity of an education edison. the 11-year-old from ft. lauderdale and his family huddled in a closet as hurricane wilma whipped overhead in 2005. watching as the storm brought flooding damage and death. so peyton, who's been solving math problems since he was three, set off to solve a problem all by himself. >> you want to start by going to the science room that i set up upstairs? >> reporter: yes. okay. his invention? a sand less sand bag. >> so i used salt in my bag. and i used that so that the water inside my bad would be heavier than any approaching water. do you have any idea what he's saying? >> no, not really. >> reporter: but here's the tlangs. regular sandbags are heavy. peyton's are lighter, making them easier to carry. that's because they're filled with chemicals and salt and only expand when doused with water. and that also means less water gets through the cracks. >> when you add it to water, it

. >> i'm peyton robertson. >> reporter: peyton robertson has the enthusiasm of an infomercial king. is in his audition tape for this year's young scientist contest. with the ingenuity of thomas edison. the 11-year-old from ft. lauderdale and his family huddled in a closet as hurricane wilma whipped overhead in 2005. watching as the storm brought flooding damage and death. so peyton, who's been solving math problems since he was three, set off to solve a problem all by himself. >> you want to start by going to the science room that i set up upstairs? >> reporter: yes. okay. his invention? a sandals sand bag. >> so i used salt in my bag. and i used that so that the water inside my bad would be heavier than any approaching water. do you have any idea what he's saying? >> no, not really. >> reporter: but here's the translations. regular sandbags are heavy. peyton's are lighter, making them easier to carry. that's because they're filled with chemicals and salt and only expand when doused with water. and that also means less water gets through the cracks. >> when you at it to water, it ex

remember the name peyton robertson. he is going to be very famous and rich. >> and a pitchman as well. >> still ahead we're now 100 days from the winter olympics in sochi. we're going to show you the ongoing efforts to get the city ready plus some of the new supported added to the game. >> the all-time home of barry bonds is back in the headlines. what he is asking a court to consider. >> and getting over the san mateo bridge you'll notice traffic is moving smoothly. we'll get you up to the bay bridge, check out some of the other bridges. today marks 100 days until the winter olympics in russia. the games are expected to be the most expensive winter olympics in history with the current overall price tag at $51 billion. almost all of the olympic venues have been built from scratch and most of the sports facilities have been completed. there will be 12 new events at this olympics including women's ski jumping, and slope style snowboarding. when the time comes you can watch all of the action right here on nbc bay area. >>

. >> reporter: peyton robertson has the enthusiasm of an infomerical king.reated a prototype. >> reporter: the 11-year-old from ft. lauderdale and his family huddled in a closet as hurricane wilma ripped over in 2005 watching as the storm brought flooding damage and death. peyton who's been solving math problems since he was 3 set off to solve a problem by himself. >> you want to start with the science room i set up upstairs. >> reporter: yes. >> okay. >> reporter: his invention a sandless sandbag. >>> i use salt in my bag. so it would be heavier than any approaching water. >> any idea what he is saying. >> no. >> here's the translation, regular sandbags are heavy, peyton's are lighter making them easier to carry because they are filled with chemicals and salt and only expand when doused with water and less water gets through the cracks. >> when you add it to water it expands. >> whoa. >> reporter: like any scientist, peyton knows that field tests are a must. i'm safe behind your barrier here. >> reporter: engineers say peyton's invention is a real deal. >>

. >> the 2013 top young scientist is peyton robertson. [ applause ] >> and peyton is here, along withird place winners. we have peyton and brooke and sirjay. they're all here. welcome to the show, first of all. >> thank you. >> peyton, you won it all, $25,000? >> yes, sir. it's a lot of money. i'll did i have netly save it for college. >> not buying a car? >> i'm not old enough for that. i'll save it for college. the top four finalists get to go to costa rica. it's also a science based trip. you learn about biology, ecology, and stuff like that. >> so all three of you are going to costa rica. what is your thing? what did you invent? >> this is my animation. i had a sand bag. >> instead of getting a sand bag when we have a flood, listen to how dumb -- when you have a flood and you have a sand bag. why a polymer and salt? why is that better? >> polymer, when dry, it's light weight. when it's exposed to water it gets heavy. dry it's 4 pounds and you get it wet, it's 30 pounds. >> what he said. >> so how would it work? this is the bag itself? >> this is the bag itself. i used a system to