Hey there, Smarty Pants. Welcome to Smarty Cues, where I, the trusty narrator, answer questions from you, the Smarty Pants.

Today we're talking about magnets, numbers, clouds, doors, and more. So let's jump in and get smarted.

Our first question comes from Liam, age six, in Texas, who asks,

why do magnets only stick to certain kinds of metals? Great question, Liam. Magnets don't

stick to all metals, only certain ones like iron, nickel, and cobalt. That's because of how

the atoms inside those

metals are arranged. Inside these special metals are tiny regions called magnetic domains. When those

domains line up, they create a magnetic field. Magnets can pull on those aligned domains, which is why

they stick so well to those materials. Other metals like

aluminum or copper don't have their atoms arranged in the same way, so magnets don't stick to them.

So it's not about how metal something is, it's about how its atoms are organized inside.

Our next question comes from Kevin, age eight, in Philadelphia, who asks, are plankton the smallest

animals? Awesome question. Plankton are tiny living things that float or drift in water, but not all

plankton are animals. There are two main types, zooplankton, which are tiny animals, and phytoplankton,

which are more like plants and make their own food

using sunlight. Some plankton are extremely small, even microscopic, but they're not the smallest

animals. There are even tinier organisms like certain single-celled creatures that are smaller

than many plankton. So while plankton include some of the smallest animals,

they're not the smallest of all.

Next up, we've got a question from Kevin's little sister, Nora, age five,

who asks,

Why do numbers go on forever?

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