Everyone said it couldn't be done. But three teen girls from Ireland recently proved them all wrong with a science fair experiment that not only landed them the top prize at the Google Science Fair, it may also help to end the world food crisis.

Ciara Judge, Sophie Healy-Thow, and Émer Hickey have always been interested in science and gardening, but they never could have expected how far the two interests would take them.

It all started one day when Hickey was gardening with her mom. She found strange nodules covering a pea plant and took the specimen into her science teacher to find out what they were. Hickey's teacher explained that the nodules contained a nitrogen-fixing bacteria known as rhizobia, which converts atmospheric nitrogen into organic compounds, like ammonia, that are beneficial for the plant.

Hickey mentioned the discovery to her friends, Judge and Healy-Thow, and the three girls wondered if these rhizobia might also be used to boost food production for other plants, possibly playing some sort of role in the world food crisis — an issue that the girls were learning about in school. Their teachers said it couldn't be done, but the teens were not discouraged.

They started conducting research on their idea using home laboratory equipment and soon discovered that it was not only possible, it might just change the world. After 11 months and 125 experiments on more than 9,500 seed samples and more than 120,000 manually recorded measurements, Hickey, Judge and Healy-Thow found that rhizobia increased the rate at which seeds germinated by an average of about 50 percent and increased crop yield by as much as 74 percent. It worked on pea plant seeds but also on barley and oats.

It's better when they explain it:

The girls' idea and diligence not only won them the top prize in their age group at the Google Science Fair, it also earned them the grand prize for the whole competition.

The grand prize includes a 10-day trip to the Galapagos Islands and $50,000 in scholarships.