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Digital SAT practice
Reach your peak.
A quick run every day, an explanation for every question, and full-length tests on official timing.
Free, no card. You also get 36 practice questions a day: 12 easy, 12 medium and 12 hard.
The DailySTEP 1
- Three hearts. A miss costs one.
- Streaks pay. ×2 from three in a row, ×3 from six.
- Your longest streak. Beat it tomorrow.
Full-length tests
The real test, rehearsed.
98 questions across four modules, in the digital SAT’s order and on its timing, with a highlighter, a question map and a timer you can see.
How it works
One run a day. One skill at a time.
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1
Play the Daily.
A quick run with three hearts. String right answers together and the questions get harder and the points multiply.
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Miss one, learn why.
Every question is tagged by domain and skill, and every answer comes with an explanation.
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Drill that skill.
Practice any single skill at any difficulty, or just the questions you got wrong.
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Beat your best.
Come back tomorrow and climb. Progress shows your accuracy and your strongest skills.
Built around the real SAT blueprint.
Every question is tagged by section, domain, skill and difficulty, so you can practice exactly what you need. Full tests run like test day: two Reading & Writing modules, a break, then two Math modules.
Free daily practice
12 easy, 12 medium and 12 hard questions free every day, each with a full explanation. Filter by section, domain, skill and difficulty. Resets at midnight.
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Take any test on official timing, extended 1.5× time, or untimed to focus purely on accuracy.
Adaptive full-length tests
Four modules in official order. The second module of each section adapts to how you did on the first.
Vocabulary
1,023 essential SAT words. Browse the list, flip flashcards, or quiz yourself.
Your progress
Accuracy across daily practice and full tests, your strongest skills, and the ones that need the most help.
Games
PEAK Survivor, Hole and Peak Defense: three games powered by SAT practice questions.
Explanations
Every answer, explained.
Not just the right letter: how to get there, and why the tempting answer is wrong.
MathProblem-Solving and Data AnalysisHard
A store raises the price of a jacket by 20%. Later, it lowers the new price by 20%. The final price is what percent of the original price?
A80%
B96%Correct
C100%The trap
D104%
Check with $100: $100→then$120→then$96
Turn each change into a multiplier.
Up 20% means × 1.20. Down 20% means × 0.80.
Apply them in order.
1.20 × 0.80 = 0.96
Read the answer.
The final price is 96% of the original. That’s B.
Why not 100%?
The 20% cut is taken from the higher price, so it removes more than the 20% increase added.
Test day
What test day looks like.
Every Peakscor full test follows this order. In the standard tests, the second module of each section adapts to how you did on the first.
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Reading & Writing · Module 1
27 questions32 min
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Reading & Writing · Module 2
27 questions32 min
Adapts to how you did on Module 1. -
Break
10 min
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Math · Module 1
22 questions35 min
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Math · Module 2
22 questions35 min
Adapts to how you did on Module 1.
98 questions · 2 hr 14 min of testing, plus the break
Peakscor by the numbers
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FAQ
Questions, answered.
The Daily, plus 36 practice questions every day: 12 easy, 12 medium and 12 hard, each with a full explanation. Full-length Test A, Challenge Test 1 and all 1,023 vocabulary words are free too. No card needed.
Pro is $20 a month or $200 a year: unlimited practice with no daily limit, plus every full-length test and Challenge test. Peak is $29 a month or $280 a year: everything in Pro, plus the full Learn course and Peak Plan. Cancel anytime from your account.
98 questions across four modules, in the digital SAT’s order: Reading & Writing Module 1 and Module 2 (27 questions each), a 10-minute break, then Math Module 1 and Module 2 (22 questions each). On official timing that’s 2 hr 14 min of testing. You get estimated section scores and a total at the end.
Yes. In the standard full-length tests, Module 2 of each section is the harder version if you get 60% or more of Module 1 right, and the easier version if you don’t. Challenge tests use the hardest material throughout.
Official timing, extended 1.5× time, or untimed, on every test, including the free ones. Extended time allows 48 minutes for each Reading & Writing module and about 52 for each Math module. Untimed removes the clock so you can focus on accuracy.
A quick run with three hearts. Each right answer builds your streak: the questions get harder as it grows, and your points multiply (×2 from three in a row, ×3 from six). A miss costs a heart and drops you back to easy. Best is your longest streak.
Every day at midnight. You get a fresh 12 easy, 12 medium and 12 hard.
No. Peakscor is an independent SAT practice tool, not affiliated with the College Board. Scores shown are estimates.
Your next point starts today.
Free, no card.
Evaluating statistical claims · Lesson 4
What a study's design lets you conclude
Every study-conclusion question comes down to two separate questions. Were the subjects randomly assigned to groups? That decides whether you can conclude cause and effect. Were the subjects randomly selected from a population? That decides who you can apply the result to.
The two don't depend on each other. A study can use one, both or neither, so check each one separately.
A common setup: volunteers who are randomly assigned. Random assignment supports a cause-and-effect conclusion, but the volunteers weren't randomly selected from any larger group, so the conclusion is about the volunteers in the study.
The right answer claims exactly what the design supports. Wrong answers claim too much (causes without random assignment, all adults without random selection from all adults) or too little (no conclusion is possible, or only an association, when the design supports more).
| How subjects were chosen | Randomly assigned to groups | Not randomly assigned |
|---|---|---|
| Randomly selected from a population | Cause and effect, for that whole population | Association only, for that whole population |
| Not randomly selected (volunteers, convenience) | Cause and effect, for the subjects studied | Association only, for the subjects studied |
Worked example Medium
A sleep researcher recruited 86 adult volunteers through an online ad. She randomly assigned 43 of them to use a phone app that dims screen light at night and the other 43 to use their phones normally. After four weeks, the volunteers who used the app fell asleep significantly faster, on average.
Which conclusion is best supported by the study?
- Using the app causes adults in general to fall asleep faster.
- No conclusion can be drawn, because the volunteers answered an online ad.
- The app is linked to falling asleep faster, but not shown to cause it.
- For the volunteers in the study, using the app caused them to fall asleep faster.Answer
How to solve it
- Random assignment? Yes: the researcher assigned the app at random. So cause and effect is supported.
- Random selection? No: the subjects were volunteers who answered an ad. So the conclusion applies to the volunteers studied, not to adults in general.
- Match the choice that says caused and limits itself to the volunteers.
Why each choice is right or wrong
- A. Incorrect. The volunteers weren't randomly selected from all adults; people who answer an online ad to join a study may differ from adults in general. The causal conclusion can't be stretched that far.
- B. Incorrect. Being volunteers limits who the result applies to; it doesn't wipe out the conclusion. Random assignment still supports cause and effect for these volunteers.
- C. Incorrect. This claims too little. The app was randomly assigned, so the study supports more than an association.
- D. Correct. Random assignment supports cause and effect, and because the subjects were volunteers, the conclusion is limited to the volunteers in the study.
Worked example Hard
A school district has 3,000 high school students. Researchers randomly selected 200 of them from the district's enrollment list, then randomly assigned 100 of the 200 to a twice-weekly peer tutoring program in math; the other 100 had no tutoring. After one semester, the math grades of the tutored students had risen significantly more, on average.
Which conclusion is best supported by the study?
- The program caused larger math gains for the 200 students studied, but the result can't be applied to the district's other students.
- The program is associated with larger math gains, but cause can't be concluded, since the students were randomly selected.
- The program would likely cause larger math gains for the district's high school students in general.Answer
- The program would likely cause larger math gains for high school students in the whole country.
How to solve it
- Random assignment? Yes: 100 of the 200 were randomly assigned to tutoring. Cause and effect is supported.
- Random selection? Yes: the 200 were randomly selected from the district's enrollment list. The result generalizes to the district's high school students.
- Not beyond: students outside the district had no chance of being selected.
Why each choice is right or wrong
- A. Incorrect. This claims too little. The 200 students were randomly selected from the district's enrollment list, so the result can be applied to the district's high school students.
- B. Incorrect. This mixes up the two random steps. Random selection is about who the result applies to; the random assignment to tutoring is what supports cause and effect, and the study used it.
- C. Correct. Random assignment supports cause and effect, and random selection from the district's enrollment list lets the result be generalized to that district's high school students.
- D. Incorrect. The sample came only from this district. Students elsewhere had no chance of being selected, so the result can't be stretched to the whole country.
Trap Random selection is not random assignment
A study that randomly selects people and then only asks about their habits is still observational. Random selection lets you generalize; it doesn't let you conclude cause. Before you decide, find which of the two random steps the study actually used, if any.
Trap Saying too little
Not every wrong answer overclaims. When the design supports more, choices that say less are wrong too: no conclusion can be drawn when the study does support one, only an association when the groups were randomly assigned, or the result applies only to the people studied when they were randomly selected from a larger population. Give the design full credit for what it does have.
Desmos When Desmos isn’t faster
Desmos isn't useful for these questions. The answer depends on two yes-or-no facts about the design, which you find by reading, not calculating.
A quick routine works better: underline (mentally) randomly selected from and randomly assigned to in the setup, then cross out every choice that claims more, or less, than those two facts allow.
Practice
Choose a section, then practice a whole domain or drill a single skill.
Full-length tests
Each test mirrors the digital SAT: 98 questions across four modules, 2 hr 14 min on official timing.
A little harder than the real SAT. These tests can run slightly tougher than test day, which makes them good practice: if you can handle these, the real one should feel easier. No question appears in more than one test, Challenge Tests included.
Challenge Tests Hardest of the hardest
Same 98-question format, but every question is drawn from the toughest SAT material: Challenging-tier math throughout and the hardest reading.
Vocab
Study the classic SAT vocabulary list. Browse, flip flashcards, or quiz yourself.
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