Prosthetics are big business — and they aren’t cheap. A prosthetic hand can run well into the thousands, but at a high school in Worcester, a group of students are taking matters into their own hands and creating a much cheaper alternative.

Every week, a group of high school juniors at the Massachusetts Academy of Math and Science meets for one reason: to make prosthetic hands for people in developing countries free of charge. At one table in the school’s cafeteria, Daya Sharon picks up a palm made of resin in a vibrant purple. The fingers come in three parts, just like a human hand.

“This is the beginning of the hand, right off the printer. We add in strings and screws and foam padding later but this is just the beginning right off the printer,” said Sharon.

The students print each part on their 3D printer. It takes about 27 hours total to print out the parts. Once that’s done, it’s time to assemble.

Abigail Lopresti is working on the second phase of her hand. It’s a slightly different model that's a little more sleek than the others and has futurist cyborg sensibility. She threads elastic through a finger to the base of the hand.

“Right now, I’m tying in the elastics. So, the actual elastics are what keep it upright instead of wobbling around like this," Lopresti said. "So, these two [fingers] are done.”

This group of eight is part of a nationwide project called e-NABLE, a web-based organization made up of volunteer designers, engineers and regular people from all over the world who just want to pay it forward and give a hand — literally. The majority of recipients are kids, but adult amputees wear them, too.

Student Jenna Pralat demonstrates how the final product works.

“This is what the final looks like," Pralat said. "There’s padding right here and at the top to protect their hands.”

The hand is lined with medical grade foam and the wrist is adjustable with industrial strength Velcro. The user needs to have a wrist in order for the prosthetic to work. When the wrist is flexed, its fingers curl into a grasp. This allows the prosthetic wearer to grab and pick up things.

Many schools and libraries have 3D printers, which has helped this movement gain momentum. Once these kids are done, a volunteer organization in South Carolina called the Prosthetic Kids Hand Challenge will ship the hands out to NGOs in the developing world, who will then find the right recipients and breathe new life into the meaning of ‘giving a hand.’