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Know which AP topics each student has mastered, weeks before the exam.

Fivefold turns every AP course into short lessons, study guides, and exam-style practice. As students work, you see mastery by topic and a predicted score for each of them. Students join your class free with a code.

Free to start: Unit 1 of every course is open with an account. Full courses from $139 a school year for a class of up to 35, with a 14-day trial.

BiologyUnit 3Practice question

An enzyme is heated to 60°C, then cooled back to 37°C. Its reaction rate stays near zero. Why?

Pick an answer. The data are hypothetical.

Every unit, taught and tested the way the exam does it

Each AP course follows its current College Board Course and Exam Description, unit by unit and topic by topic. Every unit comes with four things, in the order students need them.
  1. A lesson for every topic

    Short steps that teach one idea at a time, with a quick check after each so nobody moves on confused.

  2. A study guide

    The whole unit in one readable guide: essentials, key terms, worked examples, common mistakes, and how it shows up on the exam.

  3. Exam-style practice

    Questions in the exam’s own formats, charts and passages included, with an explanation for every choice. Missed questions come back later.

  4. Unit tests and mock exams

    A test for every unit, plus full mock exams with the real sections and timing. Free response is scored the way the exam scores it.

Free response, scored one rubric row at a time

Students write their answer and get it back scored in seconds: each rubric point awarded or missed, the exact words that earned it, and what would earn the rest.
  • Every task is scored against its own rubric, the same way every time.
  • You see every score, point by point, next to what the student wrote.
  • The AI reads the answer, never the student’s name or email.

Here: an original task in the style of AP Biology’s Scientific Investigation question, and a response that earns 3 of 4.

Score
3 / 4
75%

Strong experimental design answers. The justification describes the result instead of explaining it.

What worked
  • Named the variable and the reason it has to stay fixed.
  • The prediction is clear and matches the setup.
Next steps
  • When a question says justify, name the mechanism: what happens to the protein and why that changes the rate.
  1. Part (a): Independent variable

    1/1 points, full credit

    Temperature is the variable the student changes on purpose.

    From your response
    • The temperature of the water bath
    Rubric criteria

    Identifies temperature as the independent variable.

  2. Part (b): Controlled variable

    1/1 points, full credit

    Names a controlled variable and explains how it would change the result on its own.

    From your response
    • more of it would make more oxygen even at the same temperature
    Rubric criteria

    Names a variable to hold constant (hydrogen peroxide concentration or volume, amount of catalase, pH, time) AND explains that changing it would also change the oxygen produced, so the effect of temperature could not be isolated.

  3. Part (c): Prediction

    1/1 points, full credit

    Correct direction, compared with the right control.

    From your response
    • Less oxygen would be produced
    Rubric criteria

    Predicts that less oxygen (or none) is produced than with unheated catalase.

  4. Part (d): Justification

    0/1 points

    This restates the prediction. It does not say what heat does to the enzyme, or why the effect lasts after cooling.

    From your response
    • the enzyme works slower when it gets hot
    To earn the missing point

    Say that 80°C denatures catalase: heat breaks the bonds holding its shape, the active site no longer fits hydrogen peroxide, and cooling does not restore it.

    Rubric criteria

    Explains that heating denatures catalase: it disrupts the bonds that maintain the protein’s shape, the active site no longer binds hydrogen peroxide, and the change is not reversed by cooling. "The enzyme slows down when hot" does not earn the point.

Sample response and scoring, shown with the same view students see.

Your whole class on one screen

Mastery for every student in every unit, who studied this week, and a predicted AP score that gets sharper the more they practice. Sort any column to see who needs you first.
See everything teachers get
Sample class: mean mastery level, 0 to 4, for each student in each unit, with the predicted AP score.
StudentUnit 1Unit 2Unit 3Unit 4Unit 5Predicted
Amara O.6 of 7 days active3.8, Proficient3.4, Proficient2.9, Familiar1.6, AttemptedNo work yet4
Ben K.3 of 7 days active2.6, Familiar2.1, Familiar1.2, Attempted0.8, Just startedNo work yet3
Carlos M.7 of 7 days active3.9, Proficient3.7, Proficient3.5, Proficient2.8, Familiar1.1, Attempted5
Dana L.1 of 7 days active1.8, Attempted1.1, Attempted0.4, Just startedNo work yetNo work yet2
Eli P.5 of 7 days active3.1, Proficient2.7, Familiar2.2, Familiar1.4, AttemptedNo work yet3
Mean mastery level, 0 to 4
  • 0+Just started
  • 1+Attempted
  • 2+Familiar
  • 3+Proficient
  • 4.0Mastered
  • No work yet

Sample class with invented students.

4

Predicted AP score: 4

From mastery across the 3 units studied so far. It firms up as more units get evidence.

20/30 XP

Unit 3: Cellular Energetics

  • 3.1EnzymesMastered
  • 3.2Environmental Impacts on Enzyme FunctionProficient
  • 3.3Cellular EnergyFamiliar
  • 3.4PhotosynthesisAttempted
  • 3.5Cellular RespirationNot started

For students: a clear next step, and proof it is working

Every topic has five levels. Lessons get you to familiar; reaching mastered takes practice on your own, so a mastered topic is one you will actually know on exam day.
  • One Continue button that always takes you to the right next thing.
  • A daily goal and a streak, with no lives and no lockouts. Nothing ever stops you from studying.
  • Free with your teacher’s class code. No email needed.

Your answer keys stay in your classroom

Answers that end up in a group chat are useless to next year’s class. Everything past Unit 1 stays behind your students’ logins.
  • Only your class can open it

    Full courses open for students in a paid class, and close when the plan ends.

  • Every page is signed

    A faint watermark shows who is reading and when. Copying, printing, and right-click are off.

  • Logins stay personal

    A teacher account works on two devices at once, and mass downloading is slowed and flagged.

BiologyUnit 3Study guide

Common mistakes

  • “Cooling the enzyme fixes it.” Denaturing changes the active site’s shape, and it does not snap back when the temperature drops.
  • “Enzymes get used up.” They are catalysts. The same enzyme molecule works through reaction after reaction.
  • “A faster rate means a bigger ΔG.” Enzymes lower activation energy. The overall energy change of the reaction stays the same.

On the exam

Expect a graph of rate against temperature or pH, and a question about why the curve falls on one side.

A sample study guide page. Try copying from it; each student’s copy carries their own name and date.

Priced per course, for the students you teach

$139 a school year covers one course for up to 35 students, and your students never pay. Larger classes, extra courses, monthly billing, and purchase orders are all on the pricing page. Buying for more than 300 students or a whole department? Ask about a school plan.