ACT 
ACT Preparation
College · ACT English, Math, Reading and Science · Certificate available
622 lessons 7.5h runtime 23 units 906 links between lessons Test yourself · 23 quizzes, a mid exam, and a final
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Begin with Unit 1: English: Sentences That Hold Together. It sets the foundation for everything that follows.
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Unit 1: English: Sentences That Hold Together 26 lessons, 2 lecture parts
- 0001 What a Sentence Needs
- 0002 Subordinate Clause
- 0003 The Stand-Alone Test worked example
- 0004 Simple Sentence
- 0005 Compound Sentence: Comma and Conjunction
- 0006 Compound Sentence: Semicolon
- 0007 Semicolon With a Transitional Word
- 0008 Transitional Words Are Not Conjunctions
- 0009 Complex and Compound-Complex Sentences
- 0010 Which Idea Leads worked example
- 0011 Sentence Fragment
- 0012 Repairing a Fragment
- 0013 Comma Splice
- 0014 Run-On Sentence
- 0015 Five Ways to Fix a Comma Splice worked example
- 0016 However Between Two Clauses worked example
- 0017 Mixed Construction
- 0018 Parallel Structure
- 0019 Correlative Pairs
- 0020 Making a Series Parallel worked example
- 0021 Misplaced Modifier
- 0022 Limiting Modifiers
- 0023 Dangling Modifier
- 0024 Repairing a Dangling Opener worked example
- 0025 Fixing One Error Without Making Another worked example
- 0026 One Paragraph, Three Repairs review
Unit 2: English: Punctuation That Does a Job 28 lessons, 2 lecture parts
- 0101 Comma Before a Joining Conjunction
- 0102 Comma After an Introductory Element
- 0103 Nonessential Information
- 0104 Essential Information
- 0105 The Removal Test
- 0106 Which and That
- 0107 Essential Names
- 0108 Essential or Not: Commas Around a Clause worked example
- 0109 An Introduction and an Interruption worked example
- 0110 Serial Comma
- 0111 No Comma Between Subject and Verb
- 0112 No Comma Inside a Compound
- 0113 No Comma After a Series or Before That
- 0114 Finding the Comma With No Job worked example
- 0115 Apostrophe for Possession
- 0116 Contractions, and Where Apostrophes Never Go
- 0117 Its and It's, Whose and Who's
- 0118 Possessive or Plural worked example
- 0119 Semicolons in a Series
- 0120 Series With Commas Inside worked example
- 0121 Colon After a Complete Clause
- 0122 Colon or No Colon worked example
- 0123 Four Ways to Join Two Clauses worked example
- 0124 Dashes and Parentheses
- 0125 Matching Paired Punctuation
- 0126 Dash, Comma or Parenthesis worked example
- 0127 End Marks and the Indirect Question
- 0128 Five Decisions in One Paragraph review
Unit 3: English: Words That Agree 28 lessons, 2 lecture parts
- 0201 A Verb Agrees With Its Subject
- 0202 Compound Subjects: And, Or, Nor
- 0203 Words Between Subject and Verb
- 0204 Verb Before Subject
- 0205 Singular Indefinite Pronouns
- 0206 Plural and Variable Indefinite Pronouns
- 0207 Collective Nouns
- 0208 Finding the Real Subject worked example
- 0209 Keep the Tense Consistent
- 0210 Past Participle After Have
- 0211 Subjunctive Were
- 0212 Choosing the Verb Form worked example
- 0213 Clear Pronoun Reference
- 0214 Pronoun and Antecedent Agree in Number
- 0215 Singular They for a Person
- 0216 It and Its for a Company or Team
- 0217 They or It worked example
- 0218 Fixing Pronoun Reference in a Paragraph worked example
- 0219 Pronoun Case in Compounds
- 0220 Who and Whom
- 0221 Choosing the Case worked example
- 0222 No Shift Into You
- 0223 Adjective or Adverb
- 0224 Comparative and Superlative
- 0225 Describing Words in Context worked example
- 0226 Idiomatic Prepositions
- 0227 Testing a Preposition worked example
- 0228 One Passage, Four Agreements review
Unit 4: English: The Right Word, and No Extra Ones 26 lessons, 1 lecture part
Lecture: Watch · 29:24
- 0301 Wordiness Is Filler, Not Length
- 0302 An Action Verb for a Noun Phrase
- 0303 One Word for a Filler Phrase
- 0304 Openings With There Is and It Is
- 0305 Redundancy
- 0306 Shorter Only if Nothing Is Lost
- 0307 Cutting a Wordy Sentence in Three Moves worked example
- 0308 Spotting the Repeated Meaning worked example
- 0309 Concrete Nouns and Exact Words
- 0310 Active Voice
- 0311 When the Passive Is Right
- 0312 Active or Passive worked example
- 0313 The End Carries the Emphasis
- 0314 Moving the Key Idea to the End worked example
- 0315 Making a Sentence Precise worked example
- 0316 Register Fits the Audience
- 0317 Keep the Tone Consistent
- 0318 Biased Language
- 0319 Matching a Passage's Tone worked example
- 0320 Affect and Effect
- 0321 Than and Then, To and Too
- 0322 Their, There and They're; Your and You're
- 0323 Fewer and Less, Farther and Further
- 0324 Imply and Infer, Lay and Lie
- 0325 Choosing Between Confused Words worked example
- 0326 One Paragraph, Tightened review
Unit 5: English: Writing That Knows Its Purpose 24 lessons, 1 lecture part
Lecture: Watch · 31:29
- 0401 Every Text Has a Purpose
- 0402 Purpose and Audience
- 0403 Naming a Passage's Purpose worked example
- 0404 The Thesis
- 0405 One Main Point per Paragraph
- 0406 The Topic Sentence
- 0407 Finding the Main Point of a Paragraph worked example
- 0408 Support: Evidence
- 0409 Analysis Explains the Evidence
- 0410 Good and Weak Support
- 0411 Too Much Detail Is Weak Too
- 0412 Choosing the Strongest Support worked example
- 0413 The Most Specific Choice worked example
- 0414 Relevance: Every Sentence Serves the Point
- 0415 The Reason Is the Answer
- 0416 Should the Sentence Be Added? worked example
- 0417 Should the Sentence Be Deleted? worked example
- 0418 What a Part Does
- 0419 Naming the Function of a Sentence worked example
- 0420 Meeting a Goal
- 0421 Did the Passage Meet Its Goal? worked example
- 0422 Which Detail Fits the Audience worked example
- 0423 Revising a Paragraph for Focus worked example
- 0424 One Passage, Five Decisions review
Unit 6: English: Order, Flow and Transitions 22 lessons, 1 lecture part
Lecture: Watch · 30:17
- 0501 Patterns of Order
- 0502 Cause and Effect, Problem and Solution
- 0503 Ordering a Paragraph's Sentences worked example
- 0504 Transitions Show Relationships
- 0505 Addition, Similarity and Contrast
- 0506 Example, Cause and Time
- 0507 Choosing a Transition by the Relationship worked example
- 0508 Not Too Many Transitions
- 0509 When No Transition Is Best worked example
- 0510 Something Old, Something New
- 0511 Pointing Words Fix a Sentence's Place
- 0512 Where Does the Sentence Belong? worked example
- 0513 Transitions Between Paragraphs
- 0514 Where Does the Paragraph Belong? worked example
- 0515 Choosing a Sentence That Links Two Paragraphs worked example
- 0516 What an Introduction Does
- 0517 Choosing the Best Opening worked example
- 0518 What a Conclusion Does
- 0519 Choosing the Best Closing worked example
- 0520 Coherence: Tense, Person and Sequence
- 0521 Fixing a Paragraph's Flow worked example
- 0522 One Passage, Put in Order review
Unit 7: Math: Numbers, Ratios and Percents 34 lessons, 2 lecture parts
- 0601 The Real Number System
- 0602 Rational and Irrational Numbers
- 0603 Order of Operations
- 0604 The Distributive Property
- 0605 Product, Quotient and Power Rules
- 0606 Zero and Negative Exponents
- 0607 Simplifying With Exponent Rules worked example
- 0608 Scientific Notation
- 0609 Computing in Scientific Notation worked example
- 0610 Square Roots and Simplifying Radicals
- 0611 Like Radicals
- 0612 Rationalizing a Denominator
- 0613 Rational Exponents
- 0614 Simplifying a Radical Expression worked example
- 0615 The Imaginary Unit and Its Powers
- 0616 Adding and Multiplying Complex Numbers
- 0617 Dividing Complex Numbers worked example
- 0618 Vectors
- 0619 Matrices
- 0620 Ratio, Rate and Unit Rate
- 0621 Finding and Comparing Unit Rates worked example
- 0622 Proportions
- 0623 Solving a Proportion With Units worked example
- 0624 Percent Means per Hundred
- 0625 Comparing Numbers Written Different Ways worked example
- 0626 The Percent Equation
- 0627 Finding the Whole From a Part worked example
- 0628 Percent Change: Divide by the Original
- 0629 Percent Change, Step by Step worked example
- 0630 Tax, Discount, Mark-up, Commission and Interest
- 0631 A Discount Then a Tax worked example
- 0632 Successive Percent Changes Do Not Add
- 0633 Two Changes in a Row worked example
- 0634 One Trip, Three Tools review
Unit 8: Math: Expressions and Polynomials 22 lessons, 1 lecture part
Lecture: Watch · 27:30
- 0701 Polynomial Vocabulary
- 0702 Combining Like Terms
- 0703 Multiplying Polynomials
- 0704 The Square of a Binomial
- 0705 Sum Times Difference
- 0706 Expanding a Product worked example
- 0707 The Greatest Common Factor First
- 0708 Factoring x² + bx + c
- 0709 Factoring by Grouping
- 0710 Factoring a Trinomial With a Leading Coefficient worked example
- 0711 Factoring a Difference of Squares
- 0712 Perfect-Square Trinomials
- 0713 Sums and Differences of Cubes
- 0714 Factoring Completely worked example
- 0715 Cancel Factors, Not Terms
- 0716 Values That Make an Expression Undefined
- 0717 Simplifying a Rational Expression worked example
- 0718 Multiplying and Dividing Rational Expressions
- 0719 Adding Rational Expressions
- 0720 Adding Two Rational Expressions worked example
- 0721 Simplifying a Complex Fraction worked example
- 0722 Recognizing an Equivalent Expression worked example
Unit 9: Math: Lines, Inequalities and Systems 34 lessons, 2 lecture parts
- 0801 The Coordinate Plane and Intercepts
- 0802 The Distance Formula
- 0803 The Midpoint Formula
- 0804 Solving a Linear Equation
- 0805 Solving an Equation With Fractions worked example
- 0806 Literal Equations
- 0807 Translating Words Into Equations
- 0808 Writing a Word Problem as an Equation worked example
- 0809 Slope
- 0810 Slope-Intercept Form
- 0811 Point-Slope and Standard Form
- 0812 Horizontal and Vertical Lines
- 0813 The Line Through Two Points worked example
- 0814 Parallel and Perpendicular Slopes
- 0815 The Perpendicular Line Through a Point worked example
- 0816 Slope and Intercept in a Model
- 0817 Interpreting a Linear Model worked example
- 0818 Absolute Value Equations
- 0819 Inequalities: the Sign Flip
- 0820 Compound Inequalities
- 0821 Absolute Value Inequalities
- 0822 Solving a Linear Inequality worked example
- 0823 Solving an Absolute Value Inequality worked example
- 0824 What a System's Solution Is
- 0825 One, None or Infinitely Many
- 0826 Substitution
- 0827 Elimination
- 0828 Solving a System by Substitution worked example
- 0829 Solving a System by Elimination worked example
- 0830 A Two-Unknown Word Problem worked example
- 0831 Systems of Inequalities
- 0832 Which Points Satisfy a System of Inequalities worked example
- 0833 A Line Meets a Curve
- 0834 Two Plans, One Crossing review
Unit 10: Math: What a Function Is and Does 26 lessons, 1 lecture part
Lecture: Watch · 31:35
- 0901 What a Function Is
- 0902 Function Notation
- 0903 Function Values in Context
- 0904 Evaluating and Solving With Function Notation worked example
- 0905 The Vertical Line Test
- 0906 One-to-One and the Horizontal Line Test
- 0907 Domain
- 0908 Range
- 0909 Finding a Domain worked example
- 0910 Piecewise Functions
- 0911 Evaluating a Piecewise Function worked example
- 0912 Average Rate of Change
- 0913 Increasing, Decreasing, Maximum and Minimum
- 0914 Average Rate of Change From a Table worked example
- 0915 Composition
- 0916 Evaluating a Composition worked example
- 0917 Vertical Shifts
- 0918 Horizontal Shifts
- 0919 Reflections
- 0920 Stretches and Compressions
- 0921 The Absolute Value Function
- 0922 Writing a Transformed Function worked example
- 0923 Matching a Graph to Its Equation worked example
- 0924 Inverse Functions
- 0925 Finding an Inverse
- 0926 Finding and Checking an Inverse worked example
Unit 11: Math: Quadratics and Other Curves 32 lessons, 2 lecture parts
- 1001 The Zero-Product Property
- 1002 The Square Root Property
- 1003 Completing the Square
- 1004 The Quadratic Formula
- 1005 The Discriminant
- 1006 Choosing a Method for a Quadratic worked example
- 1007 Solving With the Quadratic Formula worked example
- 1008 Using the Discriminant worked example
- 1009 Sum and Product of the Roots
- 1010 Radical Equations and Extraneous Solutions
- 1011 Equations With Rational Exponents
- 1012 Solving a Radical Equation worked example
- 1013 The Parabola
- 1014 Axis of Symmetry
- 1015 Vertex Form
- 1016 Maximum and Minimum
- 1017 Completing the Square to Vertex Form worked example
- 1018 Finding a Maximum in a Word Problem worked example
- 1019 End Behavior
- 1020 Zeros and Multiplicity
- 1021 Degree, Zeros and Turning Points
- 1022 Reading Zeros From a Graph worked example
- 1023 The Remainder Theorem
- 1024 The Factor Theorem
- 1025 Using the Factor Theorem worked example
- 1026 Vertical Asymptotes and Holes
- 1027 Horizontal Asymptotes
- 1028 Analyzing a Rational Function worked example
- 1029 Direct Variation
- 1030 Inverse and Joint Variation
- 1031 Solving a Variation Problem worked example
- 1032 A Ball in the Air review
Unit 12: Math: Exponentials and Logarithms 22 lessons, 1 lecture part
Lecture: Watch · 29:54
- 1101 Exponential Functions
- 1102 Growth and Decay
- 1103 Growth Factor and Growth Rate
- 1104 Writing a Model From a Percent Change worked example
- 1105 Linear or Exponential
- 1106 Telling Linear From Exponential in a Table worked example
- 1107 Compound Interest
- 1108 The Number e
- 1109 The Exponential Graph
- 1110 What a Logarithm Is
- 1111 Common and Natural Logarithms
- 1112 Evaluating Logarithms worked example
- 1113 Product, Quotient and Power Rules
- 1114 Change of Base
- 1115 Expanding and Condensing Logarithms worked example
- 1116 The Logarithm Graph
- 1117 Solving by a Common Base
- 1118 Solving With Logarithms
- 1119 Solving an Exponential Equation worked example
- 1120 Solving a Logarithmic Equation worked example
- 1121 Half-Life and Doubling Time
- 1122 A Half-Life Problem worked example
Unit 13: Math: Angles, Triangles and Similarity 30 lessons, 2 lecture parts
- 1201 Angles and Their Measures
- 1202 Complementary and Supplementary Angles
- 1203 Vertical Angles
- 1204 Alternate Interior Angles
- 1205 Corresponding and Same-Side Interior Angles
- 1206 Finding Angles Through Parallel Lines worked example
- 1207 The Triangle Angle Sum
- 1208 The Exterior Angle
- 1209 Triangle Types
- 1210 The Isosceles Triangle
- 1211 Finding Angles in a Triangle Figure worked example
- 1212 Congruent Triangles
- 1213 SSS, SAS, ASA and AAS
- 1214 Hypotenuse-Leg, and Two Tests That Fail
- 1215 Which Triangles Are Congruent worked example
- 1216 Parallelograms
- 1217 Rectangles, Rhombuses, Squares and Trapezoids
- 1218 Using Quadrilateral Properties worked example
- 1219 Similar Triangles
- 1220 Solving Similar Triangles for a Side worked example
- 1221 Similar Triangles in the World worked example
- 1222 The Pythagorean Theorem and Its Converse
- 1223 Pythagorean Triples
- 1224 Using the Pythagorean Theorem worked example
- 1225 The 45-45-90 Triangle
- 1226 The 30-60-90 Triangle
- 1227 Special Right Triangle Sides worked example
- 1228 Scale Factor for Area and Volume
- 1229 Applying a Scale Factor worked example
- 1230 One Figure, Five Facts review
Unit 14: Math: Area, Volume, Circles and Trigonometry 32 lessons, 2 lecture parts
- 1301 Rectangles and Triangles
- 1302 Parallelograms and Trapezoids
- 1303 Composite Figures
- 1304 Circumference and Area of a Circle
- 1305 Area of a Shaded Region worked example
- 1306 Tangent and Radius
- 1307 Arcs and Sectors
- 1308 Arc Length and Sector Area worked example
- 1309 The Inscribed Angle
- 1310 Using an Inscribed Angle worked example
- 1311 Rectangular Solids
- 1312 Cylinders
- 1313 Spheres and Cones
- 1314 Volume and Surface Area of a Solid worked example
- 1315 The Circle Equation
- 1316 Finding a Circle's Center and Radius worked example
- 1317 Parabola, Ellipse and Hyperbola
- 1318 Sine, Cosine and Tangent
- 1319 Choosing the Ratio worked example
- 1320 Solving Right Triangles
- 1321 Angles of Elevation and Depression
- 1322 A Right-Triangle Trig Problem worked example
- 1323 Reciprocal Functions
- 1324 Radians
- 1325 The Unit Circle
- 1326 Exact Values on the Unit Circle worked example
- 1327 The Pythagorean Identity
- 1328 Using the Pythagorean Identity worked example
- 1329 Amplitude and Period
- 1330 The Laws of Sines and Cosines
- 1331 Which Law to Use worked example
- 1332 A Silo: Cylinder Plus Hemisphere review
Unit 15: Math: Data, Chance and Counting 34 lessons, 2 lecture parts
- 1401 Population and Sample
- 1402 Sampling Methods
- 1403 Bias
- 1404 Bar Graphs and Histograms
- 1405 Box Plots
- 1406 Reading a Display worked example
- 1407 Mean, Median and Mode
- 1408 Weighted Average
- 1409 The Score Needed for an Average worked example
- 1410 Outliers and Skew
- 1411 Range and Interquartile Range
- 1412 Finding the Median and Quartiles worked example
- 1413 Standard Deviation as Spread
- 1414 Percentiles
- 1415 What a New Value Does worked example
- 1416 Scatter Plots and Association
- 1417 Line of Best Fit
- 1418 Interpolation and Extrapolation
- 1419 Correlation
- 1420 Predicting From a Line of Best Fit worked example
- 1421 Probability Basics
- 1422 Independent Events
- 1423 Mutually Exclusive Events and the Addition Rule
- 1424 The Chance of At Least One worked example
- 1425 Or, With an Overlap worked example
- 1426 Conditional Probability and Two-Way Tables
- 1427 Conditional Probability From a Table worked example
- 1428 Expected Value
- 1429 The Multiplication Principle
- 1430 Permutations and Combinations
- 1431 Permutation or Combination worked example
- 1432 Arithmetic and Geometric Sequences
- 1433 Finding a Term of a Sequence worked example
- 1434 One Class, Four Questions review
Unit 16: Reading: What the Text Says and Means 34 lessons, 2 lecture parts
- 1501 Two Kinds of Passage
- 1502 Previewing a Passage
- 1503 Reading Actively
- 1504 Surface Meaning and Implied Meaning
- 1505 Answer From the Text
- 1506 Literal and Inference Questions
- 1507 Inference: Supported, Not Stated
- 1508 Answering an Inference Question worked example
- 1509 Topic and Main Idea
- 1510 The Central Idea of a Passage
- 1511 Main Idea Versus Purpose
- 1512 The Main Idea of a Paragraph
- 1513 Too Broad, Too Narrow
- 1514 Finding the Central Idea worked example
- 1515 Supporting Details
- 1516 Locating a Detail
- 1517 A Detail Question worked example
- 1518 Summary
- 1519 Choosing the Best Summary worked example
- 1520 Sequence and Time Order
- 1521 Flashbacks
- 1522 A Sequence Question worked example
- 1523 Cause and Effect
- 1524 A Cause-and-Effect Question worked example
- 1525 Comparison and Contrast
- 1526 A Comparison Question worked example
- 1527 Characters and Their Interactions
- 1528 Reading a Character worked example
- 1529 Symbols
- 1530 Theme
- 1531 Identifying a Theme worked example
- 1532 A Literary Narrative Passage review
- 1533 An Informational Passage: Social Science review
- 1534 An Informational Passage: Humanities review
Unit 17: Reading: How the Text Is Built 26 lessons, 1 lecture part
Lecture: Watch · 30:01
- 1601 Words in Context
- 1602 Definition and Restatement Clues
- 1603 Synonym, Antonym and Example Clues
- 1604 The Substitution Test worked example
- 1605 Simple and Complex Language
- 1606 Dialect
- 1607 Word Choice Sets Tone
- 1608 Formal and Informal Voice
- 1609 The Effect of a Word or Phrase worked example
- 1610 Identifying Tone worked example
- 1611 Sentence Length and Rhythm
- 1612 Paragraph Length as a Choice
- 1613 How a Passage Is Organized
- 1614 What a Paragraph Does worked example
- 1615 How the Whole Passage Is Structured worked example
- 1616 The Purpose of a Passage worked example
- 1617 First-Person Narrators
- 1618 Second Person
- 1619 Third-Person Narrators
- 1620 The Narrator Is Not the Author
- 1621 What the Narrator Knows worked example
- 1622 Characters' Points of View
- 1623 The Author's View and Reported Views
- 1624 Sources and Their Perspectives
- 1625 Whose View Is This? worked example
- 1626 A Passage Read for Craft review
Unit 18: Reading: Arguments, Evidence and Paired Text 20 lessons, 1 lecture part
Lecture: Watch · 26:40
- 1701 Claims
- 1702 Evidence: Facts, Judgments and Testimony
- 1703 Fact and Opinion
- 1704 Is It Fact or Opinion? worked example
- 1705 Three Appeals
- 1706 Credible Sources
- 1707 How an Argument Is Built
- 1708 Does the Evidence Support the Claim? worked example
- 1709 Gaps in Reasoning
- 1710 What an Author Leaves Out
- 1711 Spotting a Gap in Reasoning worked example
- 1712 Reading Two Passages Together
- 1713 Agreement and Difference Across Texts
- 1714 The Paired-Passage Method worked example
- 1715 How Would One Author Respond? worked example
- 1716 Visual Information in a Passage
- 1717 Linking a Graphic to the Text
- 1718 Reading a Chart With a Passage worked example
- 1719 What Would Strengthen the Claim? worked example
- 1720 A Natural-Science Passage With a Chart review
Unit 19: Science: Reading Scientific Data 24 lessons, 1 lecture part
Lecture: Watch · 29:36
- 1801 The Three Science Formats
- 1802 Reading a Table
- 1803 Finding a Value in a Table worked example
- 1804 Reading a Line Graph
- 1805 Bar Graphs in Science
- 1806 Graphs With More Than One Series
- 1807 Reading a Value From a Graph worked example
- 1808 Scatter Plots of Measurements
- 1809 Trends
- 1810 Direct and Inverse Relationships
- 1811 Maximum and Minimum
- 1812 Describing a Trend worked example
- 1813 Interpolation in Data
- 1814 Extrapolation in Data
- 1815 Interpolating a Value worked example
- 1816 Extrapolating a Trend worked example
- 1817 Units and Scale
- 1818 Estimating Without a Calculator
- 1819 Quick Arithmetic From Data worked example
- 1820 Translating a Table Into a Graph
- 1821 Matching a Table to a Graph worked example
- 1822 Two Figures, One Variable
- 1823 Combining Two Figures worked example
- 1824 A Data Representation Passage review
Unit 20: Science: Experiments 28 lessons, 2 lecture parts
- 1901 The Scientific Method
- 1902 Hypothesis
- 1903 Prediction
- 1904 Science Tests, It Does Not Prove
- 1905 Which Hypothesis Was Tested? worked example
- 1906 Independent and Dependent Variables
- 1907 Treatments and Experimental Units
- 1908 Controlled Variables
- 1909 Identifying the Variables in a Study worked example
- 1910 The Control Group
- 1911 Control Group Versus Controlled Variables
- 1912 Finding the Control worked example
- 1913 One Change at a Time
- 1914 Random Assignment
- 1915 Confounding Variables
- 1916 Spotting a Confound worked example
- 1917 The Placebo
- 1918 Blinding
- 1919 Observational Study Versus Experiment
- 1920 Experiment or Observational Study? worked example
- 1921 Repeated Trials and Sample Size
- 1922 Reading a Research Summary
- 1923 Comparing Experiments
- 1924 Reading Two Experiments Together worked example
- 1925 Predicting Another Trial worked example
- 1926 Modifying an Experiment worked example
- 1927 Does the Result Support the Hypothesis? worked example
- 1928 A Research Summary review
Unit 21: Science: Evaluating Models and Viewpoints 22 lessons, 1 lecture part
Lecture: Watch · 27:04
- 2001 No Single Method
- 2002 Hypothesis and Theory
- 2003 Models
- 2004 Inductive Reasoning
- 2005 Deductive Reasoning
- 2006 Descriptive and Hypothesis-Based Science
- 2007 Inductive or Deductive? worked example
- 2008 Evidence That Supports a Claim
- 2009 Evidence That Weakens a Claim
- 2010 Testable Claims
- 2011 Which Finding Supports the Claim? worked example
- 2012 Which Finding Would Weaken It? worked example
- 2013 Association and Cause in Science
- 2014 Can the Data Show Cause? worked example
- 2015 Conflicting Viewpoints
- 2016 Shared Ground
- 2017 What Each Viewpoint Explains
- 2018 Summarizing Each Viewpoint worked example
- 2019 Where the Viewpoints Agree and Differ worked example
- 2020 New Evidence Decides
- 2021 Which Viewpoint a New Finding Supports worked example
- 2022 A Conflicting Viewpoints Passage review
Unit 22: Science: Science You Are Expected to Know 30 lessons, 1 lecture part
Lecture: Watch · 26:25
- 2101 The Cell
- 2102 Photosynthesis
- 2103 Cellular Respiration
- 2104 DNA and Genes
- 2105 Dominant and Recessive Alleles
- 2106 Predicting Offspring With a Punnett Square worked example
- 2107 Natural Selection
- 2108 Food Webs and Energy Flow
- 2109 Atoms, Elements and Compounds
- 2110 Chemical Reactions and Conservation of Mass
- 2111 Reaction Rates
- 2112 States of Matter and Phase Changes
- 2113 Density
- 2114 Solutions and Concentration
- 2115 Density and Concentration Problems worked example
- 2116 Acids, Bases and pH
- 2117 Speed, Velocity and Acceleration
- 2118 Newton's Laws of Motion
- 2119 Kinetic and Potential Energy
- 2120 Following Energy Through a System worked example
- 2121 Waves
- 2122 Electric Circuits
- 2123 Heat and Temperature
- 2124 Gravity and Orbits
- 2125 The Seasons
- 2126 The Solar System
- 2127 The Water Cycle
- 2128 The Rock Cycle
- 2129 Plate Tectonics
- 2130 Using Background Knowledge in a Passage worked example
Unit 23: Capstone: Test Day 18 lessons, 1 lecture part
Lecture: Watch · 29:19
- 2201 The Sections and Their Timing
- 2202 No Penalty for Guessing
- 2203 Unscored Questions
- 2204 Pacing
- 2205 Easy Questions First
- 2206 Best Answer and Correct Answer
- 2207 No Change Is a Real Answer
- 2208 NOT and LEAST Questions
- 2209 Budgeting Time in a Section worked example
- 2210 Eliminating to an Educated Guess worked example
- 2211 An English Question From Start to Finish worked example
- 2212 A Math Question From Start to Finish worked example
- 2213 A Reading Passage Plan worked example
- 2214 A Science Passage Plan worked example
- 2215 An English Passage, Worked review
- 2216 A Mixed Math Set review
- 2217 A Reading Passage Set review
- 2218 A Science Research Summary Set review
Who this subject is for
- Students preparing for the ACT English, Math, Reading and Science exam
- High school juniors and seniors
- Students retaking the ACT
- Homeschool students
- Adult learners heading to college
- Anyone reviewing high school English, math, reading and science
Why ACT Preparation matters
The ACT measures the English, math, reading and science skills built across high school, and many colleges use it in admissions. It prepares you for:
- College composition
- College Algebra
- Statistics
- Lab sciences
Time to complete
- of lessons (622, measured)
- 7.5 h
- of lectures (34)
- 13.7 h
- learning hours on the certificate, with quizzes and the final
- 29 h
Times are measured from the recordings and the exam time limits. Go at your own pace; nothing expires.
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