Flat Disc

Screenplay Description
The tray has ejected. We hear him running up the stairs. He enters, heads straight to the Maker. This time he pulls out a FLAT DISC a few millimeters thick. It's 7 inches wide and like the Funnel has a center hole.

Life Cycle
It appears that after an unspecified duration of time, the Flat Disc will transform into a Funnel. The screenplay seems to indicate that the Flat Disc requires light (not necessarily natural light), in order to transform. The camera is pointed at a Funnel in mid-growth, placed directly under a desk light.

Early in the screen play, Hector mistakes a Controller for a Flat Disc, and attempts to trade with Euclid, when it doesn't transform. We learn later on in the screenplay that this is, in fact, a Controller.

Transformation from Disc to Funnel
The transformation is described as follows: We see the time-lapse video he shot. A Disc does nothing for a few seconds and then begins to rise slowly. A moment later it speeds up exponentially and shoots into the Funnel shape like a biscuit rising.

Disc Strength
There are other observations you can make about the transformation. The children place the flat discs in places which they believe may prevent the growth from Disc to Funnel, namely: In all four instances, the strength of the Disc's growth manages to break whatever structure it has been placed within. The nook in the tree is SPLIT now around the growing funnel The crevasse in the rock is FRACTURED and much wider now to accommodate the Funnel's growth. One mailbox has been blown off its post and hangs loosely.
 * Within a mail box
 * Inside a rock
 * Deep inside the nook of a tree
 * Inside an earth mover

Halfway to the earthmover, the SOUND OF CREAKING METAL stops him. He braces, not turning around. Suddenly, the earthmover's lifting arm BUCKLES and EXPLODES OFF like a grasshopper's leg attached to a firecracker. Later on in the screenplay, they try unsuccessfully to damage a disc using a sledge hammer.

Large Scale Attempt To Break Disc
They make one final attempt to break the flat disc. Firstly, they feed a steel chain through the Flat Disc, and then hang the chained Flat Disc on a large metal hook, attached to a crane.

So, just to be clear, it's attached as follows:

Crane --> Crane Hook --> flat disc --> Steel Chain/Cable --> Tractor positioned on a brick pile Vaughn sends the tractor off the edge of the brick pile. It in turn strains the Disc hung on what we now see is the end of a LARGE CRANE'S steel cable. The cable and chain go taut as the tractor swings a few feet off the ground. Initially, the Flat Disc seems to be strong enough to hold the tractor; however, after some further agressive tugging of the chain, the Disc suddenly breaks into fragments.

Deafness
The breakage causes temporary deafness in all of the boys. The script also tells us that the boys all incur a temperature of around 100 for a certain amount of time.

An episode of deafness is experienced later in the story, when the boys attempt to connect starbursts and flowers together.

Heat
The broken disc causes the tractor and bricks to increase to a very high temperature: CLOSE-UP: RAINDROPS hit the pile of BRICKS, instantly BOIL, and evaporate with a hiss. CLOSE-UP: The same happens when rain hits the metal of the TRACTOR.

Disposal
The boys decide to dispose of the broken disc fragments into what is described as a man-made seemingly BOTTOMLESS HOLE. They make no further attempt to break any flat discs after this incident.