Chokwe Selassie is on a mission to help drivers avoid potholes（路面坑洼）.The eighth-grader was inspired to kick off his mission on a recent morning, when his mother was driving him to school. Their car was damaged as it went over a huge pothole in the middle of the street in their hometown of Jackson,Missisippi."I decided I was going to do something about the pothole problem in my city，"Chokwe says.His solution： an app（手机应用）that warns drivers when there is a pothole ahead. Chokwe developed the app with his friends Rodriguez Ratliff and Emmanuel Brooks."When the app detects a pothole，it is highlighted（突出显示）in red，"Chokwe says."And if you get close to the pothole, your phone will warn you."Drivers can also use the app to report any potholes they encounter, and to look for other routes they can take to avoid roads that have them. The app relies on current available information about the streets of Jackson.“It works by using the city's 311 call system,so it uses information already stored in a database," Chokwe says.(79)Through the call system,citizens dial 3-1-1 to report non-emergency problems—which include potholes. Chokwe and his friends determined that focusing on the 10 busiest streets in Jackson would give them a large enough sample size to test the prototype（原型）. (80)Although the app isn't yet available for sale.Chokwe is already looking for ways to improve it. The prototype remains limited to10 streets in Jackson, but he hopes to add more, so that it includes every street in the city. And then he wants to go even farther.“I want to keep working on the app until it's nationwide,"Chokwe says.