KNOXVILLE, Tenn. — Third grade students at the Episcopal School of Knoxville built on lessons they've learned in the Innovation Lab. 

"The kids are learning about the six simple machines: the wedge, the lever, the inclined plane, the screw, the pulley, and the wheel and axle," ESK teacher Megan Jenkins said. 

Their assignment? Incorporate at least three of those machines into a delivery system for Valentines. 

A marble drops into a funnel to start the process of delivering a tiny car
A marble drops into a funnel to start the process of delivering a tiny car
WBIR

They designed Rube Goldberg style machines out of recycled and donated parts. 

"We were in the Lab and I just found these so I was trying to figure out a way to  put them together and that was the way it worked," student Megan Mewett said. 

At a demonstration Thursday, marbles and gumballs and anything round rolled down tubes and bounced off wedges to present valentine candy and prizes. 

A student at the Episcopal School of Knoxville adjusts the device he made in the Innovation Lab
A student at the Episcopal School of Knoxville adjusts the device he made in the Innovation Lab
WBIR

The students' creations feature those six simple machines: the wedge, the lever, the inclined plane, the screw, the pulley, and the wheel and axle.

It's a Valentine delivery system presentation so at the end of the journey there's a candy payoff. 

This Valentine delivery system features inclined planes and a pulley
This Valentine delivery system features inclined planes and a pulley
WBIR

As one girl explained, "The marble is going to go down the incline plane, hit the wedge, and make the Starburst launch." 

And when it launches, someone can eat it. 

A marble rolls down a series of paper towel rolls in this device a third grader created
A marble rolls down a series of paper towel rolls in this device a third grader created
WBIR

The school started the Valentine delivery system project about 15 years ago. 

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