Talking-Tube Game Kits: Follow the Weight

An Investigation at the Talking Tubes

At the playground's talking-tube station, children send number patterns to a partner through long tubes. Volunteers prepare game kits with felt squares and wooden disks. Players arrange the pieces to show the patterns they hear. Before putting out the kits, volunteer Nia investigates what happens to their total weight when the pieces are mixed together.

Nia places a digital scale on a firm, level bench and checks that its empty platform reads zero. For each trial, she measures the empty storage tub with its lid, the felt squares, and the wooden disks separately. She records the readings in grams. Then she puts the pieces in the tub, closes its lid, and gently turns the tub to mix them.

The records below show her measurements. During mixing, the same tub, lid, squares, and disks stay together. No pieces enter or leave.
Kit A: tub and lid, 24 g; felt, 36 g; wood, 60 g; whole kit after mixing, 120 g.
Kit B: tub and lid, 32 g; felt, 48 g; wood, 80 g; whole kit after mixing, 160 g.
Kit C: tub and lid, 40 g; felt, 64 g; wood, 96 g; whole kit after mixing, 200 g.

For another test, Nia uses soft modeling dough inside a tightly closed pouch. The empty pouch weighs 12 g. The pouch and dough together weigh 180 g. She presses the dough flat without opening the pouch and measures 180 g. Next, she bends the dough into a curve through the pouch and measures 180 g again. She waits for each reading to settle.

Finally, Nia investigates what happens when pieces move away from the scale. She weighs another complete kit on a tray. Some wooden disks then spill onto the bench, outside the tray. She leaves the tub, lid, and tray on the scale and records a reading. After returning the spilled disks, she records another reading. The graph in the next section shows this test.