Passage
The school's robotics club is known for the machines it sends to regional competitions, but this year it built something that stays rooted in one place: a greenhouse. The structure sits behind the gym, a frame of plastic and aluminum no bigger than a garden shed. Inside, rows of basil and lettuce grow under lights, and sensors watch over the plants day and night1, they never rest.
The system is simple in principle. Sensors measure the 2 soils moisture and temperature, and when the soil grows too dry, a small pump switches on and 3 gives water to the roots. 4 There is several sensors buried in each bed, and each of the sensors 5 report to a single computer. Buried in each bed, 6 the computer reads several sensors.
The idea began with one student. She had noticed that the cafeteria often threw out herbs that wilted before they could be used, and she wondered whether the club could grow fresher ones on site. 7 Her teammates, who had never grown anything before, were skeptical at first.
Building the greenhouse was harder than designing a robot. Students who had never handled a drill learned to frame a wall. A retired carpenter, 8 who the club invited to help, spent three Saturdays showing them how, and a teacher was responsible 9 of ordering the supplies. By the time the greenhouse was finished, the members 10 have learned to use every basic tool in the shop.
By spring the greenhouse was supplying the cafeteria with basil, lettuce, and a steady crop of cherry tomatoes. The club had learned to plant seeds, to tend seedlings, and 11 harvesting the results. The produce was fresher than the store-bought kind. 12 Nevertheless, the kitchen staff were glad to have it. Because the greenhouse grows its own herbs, the cafeteria now buys 13 less bunches of basil from the store. 14
The club now hopes to add a second greenhouse and, eventually, a small orchard of dwarf fruit trees. What began as a break from building robots has become the project the members are proudest of. 15
