Big Foam, Small Lead
Ben lifts a huge foam block out of his new bike's box. His tiny lead fishing weight sits on the floor beside it.
Does the bigger thing have more matter in it?
Page 1
Science · Grade 5 Science
Chapter 1: Matter and Its Properties
Two different questions about the same object.
Ben lifts a huge foam block out of his new bike's box. His tiny lead fishing weight sits on the floor beside it.
Does the bigger thing have more matter in it?
Make your guess to turn the page.
Still to come: 10 pages · Words to Know · What We Learned · 4 questions · Explain It in Writing · Ask and Wonder
The idea this lesson is working on — Children use size as a stand-in for amount of stuff: bigger means heavier. Ben measures both for three objects and the two lists come out in opposite orders — the foam has the most volume and the least mass. Ask: which question does each number answer, space or matter? Keeping the two apart is what density depends on next year.
Density combines them — Density is mass divided by volume. Foam here is 30 g in 1,000 mL, about 0.03 g per mL; lead is 113 g in 10 mL, about 11.3 g per mL; water is 1 g per mL. Anything less dense than water floats and anything denser sinks, which is why the foam had to be measured with a ruler instead of the jug.
About the units — A milliliter is the same volume as a cubic centimeter, so a 10 cm cube takes up 1,000 mL. Measuring volume by the water a thing pushes aside only works for things that sink and do not soak up water.