Courses
Teacher-curated, self-paced courses. Looking for a guided sequence through a full topic? See Learning Paths.
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182 courses
Second Law, Heat Engines and Entropy
Physics · High School (11–12) · Heat Engines, the Second Law and Entropy
FreeCh 11 · 3/3
Heat flows from a hot body to a cold one by itself, and never the other way. A car engine wastes most of the energy of its fuel. In this course we state the second law of thermodynamics, we find the efficiency of heat engines and the coefficient of performance of refrigerators, we learn why the Carnot engine is the best possible, and we meet entropy, which tells us the direction in which changes happen.
3Lessons12Problems3Python Labs1Question Set1Mock Test
Periodic Trends in Properties New
Chemistry · High School (11–12) · Periodic Trends, Groups and Families
FreeCh 3 · 2/2
How the size of atoms and ions, the ionisation enthalpy, the electron gain enthalpy and the electronegativity change across a period and down a group, and how they decide valence and reactivity.
3Lessons11Problems2Python Labs1Question Set1Mock Test
The Sum of an Arithmetic Progression New
Mathematics · High School (9–10), General · Sequences and Series
FreeCh 5 · 2/2
Add the first n terms of an arithmetic progression with a formula, the way young Gauss did, and use it for savings, seats, steps and stacks.
3Lessons11Problems2Python Labs1Question Set1Mock Test
Reproduction in Human Beings New
Biology · High School (9–10), General · Human Reproduction
FreeCh 6 · 2/2
The changes of puberty, the male and female reproductive systems, fertilisation and the growth of the embryo, and how people look after their reproductive health.
3Lessons10Problems2Python Labs1Question Set1Mock Test
The Periodic Table as Data New
Python Programming · High School (11–12), High School (9–10), Undergraduate, General · Chemistry by Computer, Data Analysis with pandas
FreeCh 4 · 2/2
Load the elements into a pandas table, sort and filter them, plot the periodic trends, and look for patterns: which properties go together, and which elements break the rule.
3Lessons10Problems2Python Labs1Question Set1Mock Test
The Weather Project
Statistics & Data Science · Middle Stage (6–8), High School (9–10), High School (11–12), Undergraduate, General · Averages: Mean, Median and Mode, Spread of Data, Probability and Chance
FreeCh 3 · 2/2
In this project you look at the highest temperature on each of 30 days. You show it in a table and a graph, find the centre, the spread and the chances, and write a short report with a limit. The code boxes only need Run and a few changed numbers.
3Lessons10Problems2Python Labs1Question Set1Mock Test
Averages: Class Survey Data Project
Statistics & Data Science · Middle Stage (6–8) · Averages: Mean, Median and Mode
StandardFirst lesson freeExtra course
Real survey data is never tidy. In this project you clean a class survey, compare two groups with the mean and the median, and write a short honest report. It uses only what you learned in the first three chapters. The code boxes only need Run and a few changed numbers.
3Lessons8Problems3Python Labs1Question Set1Mock Test
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Specific Heats of Gases and Thermodynamic Processes
Physics · High School (11–12) · Thermodynamic Processes and Specific Heats of Gases, Kinetic Theory of Gases
FreeCh 11 · 2/3
A gas has two specific heats, and the one at constant pressure is the larger. A gas that is compressed quickly gets hot, and a gas that is compressed slowly does not. In this course we find Mayer's relation, and we study the isobaric, isochoric, isothermal and adiabatic processes with the heat, work and change of internal energy of each.
3Lessons12Problems2Python Labs1Question Set1Mock Test
Building the Periodic Table New
Chemistry · High School (11–12) · Development of the Periodic Table, Groups and Families
FreeCh 3 · 1/2
From Dobereiner's triads to Mendeleev's gaps and Moseley's atomic numbers: how the periodic table was built, how new elements are named, and how the s, p, d and f blocks follow from electron configurations.
3Lessons11Problems2Python Labs1Question Set1Mock Test
Patterns and the nth Term New
Mathematics · High School (9–10), General · Sequences and Series
FreeCh 5 · 1/2
Spot an arithmetic progression, find its common difference, and write a formula for its nth term. Then use it to find any term, or to find which term has a given value.
3Lessons10Problems2Python Labs1Question Set1Mock Test
Reproduction in Simple Organisms and Plants New
Biology · High School (9–10), General · Reproduction in Plants, Heredity and Inheritance
FreeCh 6 · 1/2
Why the copying of DNA is never perfect, and why that matters. Fission, budding, fragmentation, regeneration, spores and vegetative propagation, then sexual reproduction in flowering plants.
3Lessons11Problems2Python Labs1Question Set1Mock Test
Moles and Reactions by Computer New
Python Programming · High School (11–12), High School (9–10), Undergraduate, General · Chemistry by Computer
FreeCh 4 · 1/2
Write a molar mass calculator that reads formulas such as Ca(OH)2, then programs for moles, the limiting reagent, the yield, and the volumes in a dilution or a titration.
3Lessons10Problems2Python Labs1Question Set1Mock Test
Chance
Statistics & Data Science · Middle Stage (6–8), High School (9–10), High School (11–12), Undergraduate, General · Probability and Chance
FreeCh 3 · 1/2
In this short course you find the probability of an event by counting, check it with a simulation, and find the chance of two things happening together. You learn why a short run of tosses can mislead and a long run does not. The code boxes only need Run and a few changed numbers.
3Lessons10Problems2Python Labs1Question Set1Mock Test