4:00
Pre-Algebra
Intro
Place Value & Decimals
Why the same digit is worth different amounts depending on where it sits.
Pre-Algebra
Pre-Algebra is where arithmetic turns into structure. Fractions, signed numbers, ratios and the first equations. Almost every student who struggles in Algebra 1 is actually still struggling with something on this list, which is why it is worth finishing properly rather than quickly.
48 topics · 7 units
48
Topics
The arithmetic and number sense algebra assumes you already have.
Numbers & Operations
10 topicsThe number system underneath everything else: place value, factors, signed numbers, and the order operations happen in.
4:00
9:53
Pre-Algebra
Intro
Factors & Multiples
Two words that get mixed up constantly, and the difference in one sentence.
11:28
Pre-Algebra
Intro
Prime Factorization
Breaking any number into the prime building blocks that only it has.
15:25
Pre-Algebra
Intro
GCF & LCM
The biggest thing that divides both, and the smallest thing they both divide.
5:20
Pre-Algebra
Intro
Order of Operations (PEMDAS)
Why 2 + 3 × 4 is 14 and not 20, and the order every calculator agrees on.
5:39
Pre-Algebra
Intro
Practice ready
Integers & Absolute Value
Negative numbers on the number line, and what the bars around a number really mean.
12:54
Pre-Algebra
Intro
Adding & Subtracting Integers
The sign rules, and the one reframing that makes them stop being rules.
5:32
Pre-Algebra
Intro
Multiplying & Dividing Integers
Why a negative times a negative is positive, not just that it is.
3:02
Pre-Algebra
Intro
Practice ready
Introduction to Exponents
Repeated multiplication, and the two exponents that look strange at first.
5:36
Pre-Algebra
Intro
Practice ready
Square Roots & Perfect Squares
Undoing a square, and why √ always hands back the positive answer.
Fractions & Decimals
8 topicsThe single biggest predictor of struggling with algebra later. Worth over-learning until it feels boring.
3:34
Pre-Algebra
Intro
Equivalent Fractions & Simplifying
Different names for the same amount, and how to find the simplest one.
7:42
Pre-Algebra
Intro
Comparing & Ordering Fractions
Three reliable ways to tell which fraction is bigger.
7:23
Pre-Algebra
Core
Practice ready
Adding & Subtracting Fractions
Why you need a common denominator here but not when multiplying.
5:06
Pre-Algebra
Intro
Multiplying Fractions
The easiest fraction operation, and why the answer gets smaller.
9:35
Pre-Algebra
Core
Dividing Fractions
Keep, change, flip — and the reason it is not an arbitrary trick.
4:26
Pre-Algebra
Intro
Mixed Numbers & Improper Fractions
Converting between the two forms, and which one to use when.
3:32
Pre-Algebra
Core
Fractions, Decimals & Percents
One quantity, three costumes, and how to switch between them fast.
4:45
Pre-Algebra
Intro
Operations with Decimals
Where the decimal point goes in each of the four operations.
Ratios, Proportions & Percents
7 topicsThe most directly useful maths in the whole sequence. Tips, discounts, unit prices, scale models, interest.
14:13
2:31
Pre-Algebra
Intro
Practice ready
Unit Rates
Making prices and speeds comparable by putting everything per one.
4:12
Pre-Algebra
Core
Practice ready
Proportions & Cross Multiplication
Two equal ratios, and the fastest way to find the missing piece.
5:22
Pre-Algebra
Core
Scale Drawings & Similar Figures
Same shape, different size, and what happens to area when you scale.
12:44
Pre-Algebra
Core
Percent of a Number
Tips, discounts, and tax without reaching for a calculator every time.
11:23
Pre-Algebra
Core
Percent Increase & Decrease
Measuring change against where it started, not where it ended.
22:06
Pre-Algebra
Core
Simple Interest
I = Prt, the formula behind loans, and how it differs from compounding.
Expressions & Equations
8 topicsWhere letters enter. This unit is the actual bridge from arithmetic into algebra.
6:55
Pre-Algebra
Intro
Variables & Expressions
What a letter is doing in a maths problem, and how to read one.
13:55
Pre-Algebra
Intro
Evaluating Expressions
Substituting a value for a variable without losing signs along the way.
4:32
Pre-Algebra
Core
Combining Like Terms
Which terms can be added together, and which only look like they can.
7:53
Pre-Algebra
Core
The Distributive Property
Multiplying across a sum, and the sign mistake that costs the most marks.
4:38
Pre-Algebra
Core
Practice ready
One-Step Equations
Undoing a single operation, and why you must do it to both sides.
5:12
Pre-Algebra
Core
Practice ready
Two-Step Equations
Unwrapping in reverse order — why the constant comes off first.
4:41
Pre-Algebra
Core
Practice ready
Writing Equations from Words
Turning a sentence into algebra — the step most word problems actually fail at.
6:24
Pre-Algebra
Core
Practice ready
Introduction to Inequalities
Solving like an equation, with one rule that has no equation equivalent.
The Coordinate Plane
4 topicsWhere numbers become pictures. Everything in Algebra 1 graphing starts here.
5:39
Pre-Algebra
Intro
Practice ready
The Coordinate Plane
Axes, quadrants, and reading an ordered pair the right way round.
2:44
Pre-Algebra
Intro
Practice ready
Graphing from a Table
Turning a rule into points, and points into a line.
8:47
Pre-Algebra
Core
Practice ready
Slope as Rate of Change
Steepness as a number, and what it means outside of maths class.
9:53
Pre-Algebra
Core
Direct Variation
The special linear relationship that always passes through the origin.
Geometry Essentials
7 topicsThe geometry that keeps appearing inside algebra problems: angles, area, and the Pythagorean theorem.
7:07
Pre-Algebra
Intro
Angles & Parallel Lines
Angle pairs that are equal, angle pairs that add to 180, and how to tell.
4:28
Pre-Algebra
Intro
Triangles & Angle Sums
Why every triangle's angles add to 180°, and the polygon version of the rule.
8:25
17:19
Pre-Algebra
Core
Circles: Circumference & Area
Two formulas that look alike and get swapped constantly.
8:07
Pre-Algebra
Core
Volume & Surface Area
Filling a solid versus wrapping it, and the formulas for each.
4:34
Pre-Algebra
Core
The Pythagorean Theorem
a² + b² = c², the single most reused formula in all of maths.
43:51
Data & Probability
4 topicsSummarising a set of numbers honestly, and measuring how likely something is.
11:37
Pre-Algebra
Intro
Mean, Median, Mode & Range
Four summaries of a data set, and when the average lies.
5:25
10:01
9:05
Pre-Algebra
Core
The Counting Principle
Multiplying choices to count possibilities without listing them.