Biology Classes for Teens

Meet the tiny living things that carry out every part of life inside just one cell.

Discover what plant and animal cells share, and the three clever extras that only plant cells carry.

Meet the bacteria, viruses, and fungi that cause disease, and discover how your white blood cells fight back.

See how antagonistic muscle pairs bend and straighten your joints, then discover how diffusion moves substances in and out of your cells.

Zoom from a single tiny cell all the way up to a whole living body, one level at a time.

Discover how your cells release energy from glucose, with oxygen and without, and why your muscles ache after a sprint.

Journey to hydrothermal vents, where whole ecosystems thrive in total darkness using chemical energy instead of sunlight.

Variation, a struggle to survive, differential survival, and heredity, the four ingredients of Darwin's big idea, and how they reshape a species over generations.

A single typo in the DNA code can do nothing, cause harm, or hand an organism a new advantage. Explore what mutations are, where they come from, and why evolution depends on them.

Follow the clues, fossils, shared bones, matching DNA, and evolution caught in the act, that together make the case for how life changes over time.

Zoom into a cell to meet DNA, the twisted ladder that codes for life, and see how genes and chromosomes carry a set of instructions from parents to you.

From coral reefs to kelp forests, discover why the variety of life keeps ecosystems stable, what services it gives us for free, and what threatens it.

Paleontologists are detectives of deep time. From a single tooth, a footprint, or a scrap of fossil dung, they rebuild whole vanished worlds. Learn how scientists piece together what ancient landscapes, animals, and food webs were really like.

Why does a spider spin a perfect web it was never taught, while a songbird must learn its tune? Explore how instinct, learning, and natural selection shape the way animals behave.

For centuries we sorted life by how it looked. Now DNA lets us read the code of life itself, revealing hidden family ties and rewriting the tree of life in astonishing ways.

History books love emperors and generals — this course studies everyone else. Examine the lives of enslaved people, women in Athens and Sparta, and conquered peoples, and ask why their voices are so hard to find.

The living world explained the way school actually teaches it: cells, DNA, heredity, evolution, body systems, ecosystems, and the unseen microbial world.

From a warm breeze to a roaring supercell: the science of how storms form.

How steam, machines, and factories rewired the modern world.

How France toppled a monarchy, chased liberty, and unleashed terror.

How thirteen colonies broke from an empire and invented a republic.

Discover how organisms, energy, and environments connect into living systems.

How life diversified from a shared ancestor through natural selection.

How a four-letter chemical code shapes every living thing, including you.

The smallest unit of life, and the busy machinery packed inside it.