All courses

30 courses and 319 lessons open today. Pick any of them, each one starts with a toy.

Artificial Intelligence

• How a Neural Network Thinks (Beginner, 10 lessons): Teach a tiny network, one example at a time, and see how it learns.
• How Language Models Work (Intermediate, 12 lessons): See how a chatbot picks every next word, reads in tokens and pays attention.
• Learning From Data (Intermediate, 11 lessons): Turn data into tables, ask the neighbors, grow decision trees and test fairly.
• How Machines See and Hear (Intermediate, 10 lessons): Pictures and sounds become grids of numbers. Watch filters find edges.
• Search, Games and Plans (Intermediate, 11 lessons): Search, game trees and plans: the AI that thinks ahead instead of learning.
• AI and Us: Using AI Well (Intermediate, 10 lessons): Bias, made up answers, deepfakes and privacy. Use AI with a clear head.
• Learning by Reward (Advanced, 10 lessons): An agent tries, fails, gets a reward and slowly learns what works.
• Inside Deep Learning (Advanced, 10 lessons): Open up a deep network: backprop, optimizers and why training goes wrong.
• Generative AI: Making New Things (Advanced, 11 lessons): From noise to a picture: how machines make new things.

Math

• Functions You Can See (Beginner, 10 lessons): Feed a machine numbers, drag lines and curves, and see how one quantity changes another.
• Algebra in Motion (Intermediate, 12 lessons): Balance scales, undo steps and slide parabolas until equations solve themselves.
• Probability by Simulation (Intermediate, 11 lessons): Flip a thousand coins, grow trees of chance and design a game that is actually fair.
• Growth: Exponents and Logs (Intermediate, 11 lessons): Watch doubling explode, run it backwards with half-life and count doublings with logs.
• Vectors and Matrices (Intermediate, 12 lessons): Arrows that move things and matrices that bend the whole grid, built by hand.
• Shapes and Proof (Intermediate, 10 lessons): Cut, slide and rearrange shapes until you can prove why the rules are true.
• Counting and Patterns (Intermediate, 11 lessons): Count choices with trees, spot the rule in sequences and topple proofs like dominoes.
• Trig and Waves (Advanced, 11 lessons): Spin the unit circle, watch sine cast its shadow and turn waves into sound.

Code

• How a Programmer Thinks (Beginner, 10 lessons): Give exact instructions, then watch variables, ifs and loops run step by step.
• Build with Python (Intermediate, 12 lessons): Write real Python: strings, loops, dictionaries and grids, up to a tic-tac-toe bot.
• How Computers Store Everything (Intermediate, 11 lessons): Flip switches into numbers, letters, pixels and sound, then squeeze, fix and hide them.
• Algorithms in Motion (Intermediate, 11 lessons): Race searches and sorts side by side and see why some algorithms grow so much faster.
• Recursion: Functions That Call Themselves (Intermediate, 11 lessons): Functions that call themselves: watch call trees grow, draw fractals and solve mazes.
• Data Structures You Can See (Intermediate, 10 lessons): Stacks, queues, hash tables and trees you can poke, then pick the right one for the job.

Physics

• How Things Move (Beginner, 10 lessons):
• Forces: Why Things Move (Intermediate, 11 lessons):
• Energy: The Universe's Currency (Intermediate, 10 lessons):
• Waves and Sound (Intermediate, 10 lessons):
• Circuits You Can Build (Intermediate, 10 lessons):
• Light and Sight (Intermediate, 10 lessons):
• Gravity and Orbits (Advanced, 10 lessons):

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