Mean, Median, Mode or Standard Deviation? Picking the Right Summary
How to find the mean, median, mode, range, quartiles and standard deviation, when each is the right summary, and how changing data affects them.
Study guides
Step-by-step guides to algebra, geometry, trigonometry, calculus, statistics and the SAT, with worked examples and practice problems. Plus study skills, and notes for teachers.
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Weighted vs. Unweighted GPA, and How to Calculate Yours
What GPA actually measures, the difference between weighted and unweighted, how credits change the result, and a worked example you can follow with your own report card.
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Three Ways to Solve a Quadratic Equation
Three methods for solving any quadratic equation, with fully worked examples, how to choose the fastest method, what the discriminant tells you, and the mistakes that cost the most points.
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The Pomodoro Technique for Students
Twenty-five minutes of focus, five minutes off. The Pomodoro Technique is simple, but most students use it wrong. How to set it up for homework, what to do on breaks, and how to adjust…
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How to Use AI for Homework Help Without Cheating Yourself
AI can explain a hard concept at midnight when nobody else is awake. It can also do your homework for you, which is the fastest way to fail the test. How to use AI…
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How to Run an Online Study Group That Doesn’t Turn Into a Hangout
Studying with friends can be the most useful hour of your week or the least. A simple plan for size, roles, timing and what to do on the call so your group actually learns…
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How to Make Flashcards That Actually Stick
Most students make flashcards, flip through them twice the night before, and forget them by Friday. Here is how spaced repetition works, how to write better cards, and a simple weekly plan you can…
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How to Learn From a Video Lesson (Instead of Just Watching It)
Watching a lesson feels like learning, but most of it is gone by the next day. Simple things to do before, during and after a video so you remember what it taught, on your…
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How to Read Position-Time and Velocity-Time Graphs
How to read position-time and velocity-time graphs: slope as velocity and acceleration, area as displacement, with worked examples and practice.
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5 Common Graphing Mistakes in Physics Labs, and How to Fix Them
Avoid the graphing mistakes that cost points on physics lab reports: wrong axes, missing units, poor scales, connecting dots and slope from data points.