At Manzo Elementary School in Tucson, Arizona, raising fish at school was one small answer to a big problem: many people in the neighborhood did not have enough food to eat.
The students could eat breakfast and lunch at school, but their families didn't always have enough money to provide dinner. Buying fresh foods, such as vegetables and meat, was difficult. Then the teachers had an idea: could the students raise food at school for the neighborhood?
The project wouldn't be easy to carry out. Tucson is in a desert, so water is a precious resource. Soil in the desert doesn't always have the nutrients plants need to grow, so the students would need to add a natural fertilizer（肥料）.
Counselor（顾问）Moses Thompson read about aquaponics, a way of growing fish and plants together for food. Hundreds of years ago, the Aztecs built "floating farms" called chinampas on the lakes outside what is now Mexico City. Inspired by that, Moses helped the school set up a system in which fish waste fertilizes plants, and the plants' roots clean the water in the fish tank.
Fish aren't the only animals that help students feed their neighbors. Chickens lay eggs. Visiting pollinators help turn flowers into beans, tomatoes and so on. "Bees and butterflies come," says Santiago, aged 10.
When the students have raised enough food, it's time for Market Day. Vegetables are available for donation to people in the neighborhood. Students sell eggs and tilapia（罗非鱼）to raise money for seeds, fish food and chicken food.
"People don't have a lot of money, so it's a nice dream we have to give them food," says Emmanuel, aged
11. "It's an opportunity to be healthy and eat better."
"We can plant good food and have fun while we're doing something important," says Blanka, aged 10. "I'm so happy to be at this school."
