The "Solve for Tomorrow" competition encourages kids in science, technology, engineering and math, also known as STEM.
They found out about the win from a video shown in class. East Valley High will get a whopping $140,000 in technology. More than two thousand schools competed.
KIMA highlighted East Valley's project that found a way to reduce energy with a cooling system using irrigation water.
The students did not expect the big win.
"We thought we really had a chance, but we didn't know if we were going to be the winners or not, and so knowing that we were was pretty exciting," said student winner Ruby Galayde.
Two students will go to Washington, D.C., where they will be honored for the win.