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Previews of the Stellar app: an AP Biology practice question with instant feedback, Nova the AI tutor, a math graphing exercise, an AMC competition question, a Bluebook-style AP Calculus mock exam and an AP Macroeconomics course path.

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A course turns into a full study system.

Open a course, move through the learning loop, and keep every support tool attached to what you are studying.

  1. AP MacroeconomicsLesson 3.8: Financial assets
    1. 1Interactive lessonLearn the idea
    2. 2VideoWatch it click
    3. 3Interactive practiceTry it now
    4. 4Infinite practiceKeep improving
    5. 5Exam-style questionsPractice the format
    6. 6Mastery examProve readiness
    01

    Open a course

    Every course is one path: lesson, video, practice, exam-style questions and a mastery exam.

  2. Core learning loopStep 1 · Interactive lesson

    Guided macro MCQ

    What happens to existing bond prices when interest rates rise?

    02

    Move through the learning loop

    Each step checks your answer straight away and explains why.

  3. Support tools stay attached

    Not the main loop, but always nearby when the course needs backup.

    • NovaAsk for help when you get stuck.
    • NotesSave ideas from lessons and practice.
    • FlashcardsReview terms that need repetition.
    • My SpaceKeep courses, folders, and study materials connected.
    • ProgressSee what is mastered and what needs work.
    • QuasarUse deeper tools when a course needs extra analysis.
    • AP Score CalculatorEstimate score targets and plan the next practice push.
    03

    Keep support tools attached

    Nova, notes, flashcards and progress stay next to what you are studying.

Interactive lessons

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AP MacroeconomicsAP Physics 1AP US HistoryAP Computer Science AAMC 8
Fiscal Policy
Changing G, representing government spending, can have a significant impact on the economy.

In country X, recently imports have increased by 50 million and government spending has decreased by 70 million. The GDP used to be 900 million. What is it now?

Choose the best option:

A$1,020 Million
B$920 Million
C$880 Million
D$780 Million
Rigid Systems
All content in this lesson is interactive. Hover over the highlighted terms to learn more about a vocabulary term.

From Units 1 to 4 of AP Physics 1, you have dealt with objects that are point particles, which have no shape. However, for Units 5 and 6, objects will now need a shape in order to fully understand rotational dynamics. These objects or systems, that now have shape, can be called rigid systems (or rigid bodies).

A rigid system is an idealized model of a solid object in which the distances between any two points on the object remain constant.

Native Americans Before European Contact
All content in this lesson is interactive. Hover over the highlighted terms to learn more about a vocabulary term.

Before contact with Europeans, Native American societies across what is now the United States and Latin America exhibited a wide range of lifestyles and cultural practices, shaped by their diverse environments and resources.

Here is an overview of the lifestyles of Native American tribes in different regions of North America, as well as the Aztec and Inca empires in Central and South America.

Mutator Methods
All content in this lesson is interactive. Hover over the highlighted terms to learn more about a vocabulary term.

Mutator methods, also called setter methods, allow us to modify private fields in a controlled and predictable way.

They help us achieve encapsulation, a principle that protects an object’s internal state and ensures its integrity by controlling how external code interacts with its data.

System of Equations
All content in this lesson is interactive. Hover over the highlighted terms to learn more about a vocabulary term.

Common methods for solving systems of equations include substitution, elimination, or matrix manipulation. In AMC 8 problems, they are typically presented as word problems involving real-world scenarios, such as determining quantities, relationships, or rates.

Success requires identifying the key relationships between variables, setting up accurate equations, and solving them efficiently within the time limit.

A lesson from AP MacroeconomicsTry it in the app

Interactive exercises

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Engage with interactive tasks like labeling, problem-solving, and simulations that make complex concepts easier to grasp and retain.

  • Graphing, labeling and simulations
  • Math, grammar, coding, economics and Chinese
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MathGrammarCodingEconomicsChinese
Math Graphing ExerciseInteractive

Please plot the function 3y = 9x + 12 on the coordinate plane. You can plot the function by simply clicking two points that are on it.

(0, 4) (-2, -2)
Your points(-2, -2)(0, 4)
HintDivide both sides by 3 first: y = 3x + 4.
Grammar Labeling ExerciseInteractive

For the sentence below, label the nouns, the action verbs, the prepositions, the conjunctions, and any adjective or participle.

During the summer festival in the town square, families enjoyed live music, food, and games while children played and watched the parade.

Interactive Coding ExercisePython

Write Python code to find the nth Fibonacci number.

Economics Guided ExerciseInteractive

The price of Coke, a substitute for Pepsi, has increased. How does this change affect the price and quantity of Pepsi? Move the supply and demand curves and complete the sentence below.

D S P Q

After the increase of Coke’s price, demand for Pepsi Shifts Right⁠, and supply for Pepsi Doesn’t Change⁠. The price of Pepsi Increases and the quantity of Pepsi Increases⁠.

Foreign Language Tracing ExerciseAP Chinese

Trace the Chinese character below.

jū鞠

Click two points, then checkTry it in the app

Infinite practice

Infinite practice questions with AI

Access limitless, AI-generated questions that provide continuous practice opportunities, ensuring you’re prepared and confident in every subject.

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Multiple ChoiceSelect AllShort Answer

Multiple Choice Question

What is the effect of an increase in government spending on aggregate demand in the economy?

AAggregate demand shifts to the right
BAggregate demand shifts to the left
CAggregate demand does not change

Select All Question

Which of these happen when government spending increases? Select all that apply.

Aggregate demand shifts to the right
Real GDP rises in the short run
Aggregate demand shifts to the left

Short Answer Question

Explain how an increase in government spending affects aggregate demand.

Government spending is part of GDP, so aggregate demand shifts to the right.

Generated on demandTry it in the app

Exam-style MCQ

Unlimited AP®, IB®, & SAT® style MCQs and practice tests

Prepare thoroughly for all AP® subjects with a variety of mock exams designed to simulate real test conditions.

  • Timed sections that feel like test day
  • Full-length mock exams for every AP®
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AP CalculusAP Physics C: E&MAP World HistoryAP CSPAP ChineseSAT English
AP Calculus · Section IMock exam

Consider the curve defined implicitly by

xy2 + ye2x = ln(x) + xy.

Find dydx at the point (1, 1).

A1 − 2e21 + e2
B2e2 − 11 + e2
C1 + 2e21 + e2
D1 − 2e21 − e2
AP Physics C: E&MMock exam

An infinitely long coaxial cable consists of a solid inner conductor of radius a carrying a steady current I uniformly distributed across its cross section. Surrounding it is a concentric cylindrical shell with inner radius b and outer radius c, carrying the return current −I.

Using Ampère’s law, find the magnitude of the magnetic field B at a radial distance r such that b < r < c.

Aμ0I(c2 − r2)2πr(c2 − b2)
Bμ0I2πr
Cμ0I(r2 − b2)2πr(c2 − b2)
D0
AP World HistoryMock exam

“In dealing with the crises of the early twentieth century, our nation has consistently prioritized the survival and expansion of its interests abroad. The Imperial ambitions of our rivals have led to increasing tensions, evidenced by their aggressions in Africa and Asia, which threaten not only our colonies but also our economic supremacy. The alliances we have forged, particularly with like-minded empires such as those in Central and Eastern Europe, are designed not merely for mutual defense but as counterweights to the hegemonic aspirations of our adversaries. However, mounting ethnic strife within these alliances, particularly in the Balkans, has made the quest for stability fragile. We must prepare our military and diplomatic channels for a potential confrontation that could emerge from these rivalries.”

Anonymous High-Ranking Official, European Empire, Address on National Security, 1912

The excerpt best illustrates which of the following underlying causes of World War I?

AThe conflict between social classes within European nations
BThe competition and conflict resulting from imperial ambitions
CThe impact of economic depression on international relations
DThe rise of communist movements in various countries
AP CSPMock exam

A construction robot is programmed to perform tasks on a building site. The following procedures are defined:

1PROCEDURE moveDistance(meters)2REPEAT meters TIMES MOVE_FORWARD()3PROCEDURE turnAngle(angle)4ROTATE(angle)5PROCEDURE constructStructure(distance, angle)6moveDistance(distance)7turnAngle(angle)8moveDistance(2)

If the robot calls constructStructure(4, 90), which of the following describes its actions?

AThe robot moves forward 4 meters, turns 90 degrees, and then moves forward 2 meters.
BThe robot moves forward 2 meters, turns 90 degrees, and then moves forward 4 meters.
CThe robot turns 90 degrees, moves forward 4 meters, and then turns again before moving 2 meters.
DThe robot moves 6 meters in total with no turns during the process.
AP Chinese · ListeningMock exam

Voice message
Now you will listen once to a voice message left for a friend.

What kind of confirmation is the speaker asking for?

AWhether to bring a dish
BIf the friend can pick up others
CWhether to arrive early
DConfirmation of attendance
SAT Reading & WritingMock exam

Text 1 The introduction of synthetic biology has the potential to revolutionize agriculture. By engineering plants to be more resilient to environmental stresses, scientists believe we can significantly increase crop yields while reducing the use of pesticides and fertilizers. This advancement not only promises economic benefits but also addresses food security concerns as the global population continues to grow.

Text 2 While synthetic biology may enhance agricultural productivity, some scholars caution about its long-term implications. An article by researchers Maria K. Stone and Jalen Rough outlines the risks of introducing genetically modified organisms (GMOs) into ecosystems. They argue that altering plant genetics can lead to unforeseen consequences, such as the disruption of local biodiversity and even the creation of new pests that can resist natural controls.

Based on the texts, how would the researchers in Text 2 most likely respond to the claims made in Text 1?

ABy agreeing that the benefits of synthetic biology clearly outweigh any risks mentioned.
BBy suggesting that economic concerns are secondary to preventing environmental disruption.
CBy emphasizing that the long-term ecological impacts of GMOs could compromise future sustainability efforts.
DBy stating that scientists should focus solely on increasing crop production without considering side effects.

Bluebook-style exam viewTry it in the app

Exam-style FRQ

Limitless AP® & IB® style FRQ practice

Master free-response questions (FRQs) with expertly crafted materials designed to mimic AP® exam formats.

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AP US HistoryAP Human GeoAP CalculusAP CSAAP English Language
Short answer · Secondary sourcesAP US History

Sources

“In the late 19th and early 20th centuries, American foreign policy was primarily defined by the pursuit of expansionism, driven by a belief in American exceptionalism and a duty to spread democracy and capitalism around the globe. This era saw the United States engage in several conflicts and interventions, including the Spanish-American War of 1898, which not only resulted in territorial acquisitions like Puerto Rico and the Philippines but also marked a significant shift in the nation's identity as a global power. This aggressive foreign policy was justified by arguments of moral obligation, presenting the annexation of overseas territories as a benevolent act aimed at uplifting less fortunate nations, thus embodying a humanitarian facade coupled with economic interests.”Source: John A. Thompson, historian, “The United States and the Age of Imperialism”, 2003

“Contrarily, the rise of American imperialism during this period can be seen as a hypocritical endeavor, masking underlying motives of economic exploitation and nationalistic fervor under the guise of moral superiority. Critics of this foreign policy argued that instead of liberating oppressed peoples, the United States sought to reproduce its own dominance in foreign lands for the benefit of American corporations and investors. The consequences of such policies were often detrimental, leading to unrest and resistance in the territories affected, as exemplified by the Philippine-American War, where the rhetoric of liberation was starkly at odds with the reality of subjugation and violence. This imperialistic approach not only contradicted the founding principles of liberty and self-determination but also illuminated the darker side of America's global ambitions, showing that the nation's self-image was often built on the subjugation of others.”Source: David S. Mason, historian, “Imperialism and American Identity”, 2010

Using the excerpts, respond to parts a, b, and c.

a. Briefly describe one major difference between Thompson’s and Mason’s interpretations of American foreign policy in the late 19th and early 20th centuries.
Thompson sees expansion as driven by a sense of mission, while Mason
b. Briefly explain how one historical event or development from 1865 to 1917 not directly mentioned in the excerpts could be used to support Thompson’s interpretation.
c. Briefly explain how one historical event or development from 1865 to 1917 not directly mentioned in the excerpts could be used to support Mason’s interpretation.
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No-stimulus FRQAP Human Geography

Prompt

The relationship between urbanization and social patterns has significant implications for both human behavior and policy planning.

A. Define urbanization in the context of human geography.
B. Describe ONE social impact of urbanization on family structures in urban areas.
C. Explain how urbanization can lead to the increased prevalence of social issues, such as crime or poverty.
D. Discuss how urban planning can address the challenges associated with rapid urbanization.
E. Explain the role of public transportation in influencing urban development and social equity.
F. Describe how suburbanization may impact the demographic characteristics of urban areas.
G. Explain the degree to which gentrification alters the cultural landscape of neighborhoods in urban settings.
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No-calculator FRQAP Calculus BC

Data

The temperature of a lake is modeled by a continuous and differentiable function, T(t), which measures the temperature in degrees Celsius at time t (in hours). The following table displays selected values of T(t) over a period of 8 hours.

t (hours)01358
T(t) (°C)1517202325
a. Using a right Riemann sum with the intervals [0, 1], [1, 3], [3, 5], and [5, 8], approximate ∫08 T(t) dt. What does this integral represent in the context of the problem?
b. According to the Mean Value Theorem for Integrals, must there exist a time c in [0, 8] such that T′(c) equals the average value of T over that interval? Justify your answer.
c. Using the average temperature calculated in part (a), estimate the total increase in temperature from t = 0 to t = 8.
d. When the temperature of the lake is 25°C, the rate of change is T′(t) = −0.5 · T(t) + 3. Calculate T′(8) and interpret the result.
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Methods FRQAP Computer Science A

Class

This question involves the TemperatureRecord class, which records daily temperatures for a week. You will write two methods that help analyze the temperature data.

public class TemperatureRecord {
    /** Daily temperatures, size 7 (one week). */
    private int[] dailyTemperatures;

    public TemperatureRecord(int[] temperatures) {
        dailyTemperatures = temperatures;
    }

    /** Average for the week, rounded to the nearest integer. */
    public int calculateAverageTemperature()
    { /* to be implemented in part (a) */ }

    /** Number of days above threshold.
     *  Precondition: -100 <= threshold <= 100 */
    public int countDaysAboveThreshold(int threshold)
    { /* to be implemented in part (b) */ }
}
Input temperaturesThresholdOutput
[70, 75, 80, 85, 90, 95, 100]804
[60, 65, 70, 75, 80, 85, 90]803
[0, -5, -10, -15, -20, -25, -30]-102
a. Write the calculateAverageTemperature method, which adds up all the temperatures in the dailyTemperatures array and divides by the number of days (7). If the sum is 0, it returns 0 as the average.
b. Write the countDaysAboveThreshold method. It iterates through the dailyTemperatures array, counts how many days have temperatures above the provided threshold, and returns the count.
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Argument essayAP English Language

Prompt

In a 2021 TED Talk, renowned author and philosopher Alain de Botton stated: “Our culture has created the illusion that the arrived-at life is a happy life. We believe that all we need to do is find our dream job, buy a house, or travel to exotic places, and we will be fulfilled. Yet true contentment comes from a deeper understanding of ourselves, our relationships, and the acceptance of life’s inherent challenges and uncertainties.”

Write an essay that argues your position on the extent to which de Botton’s claim about the pursuit of happiness and fulfillment is valid.

In your response you should do the following:

Respond to the prompt with a thesis that presents a defensible position.
Provide evidence to support your line of reasoning.
Explain how the evidence supports your line of reasoning.
Use appropriate grammar and punctuation in communicating your argument.
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AP US History short answer with secondary sources Try it in the app
Infinite competition practice

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Prepare for competitions like AMC, AIME, and F=ma with thousands of curated problems and infinite practice. Track your progress, climb leaderboards, and build your rating through a gamified system.

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Contests AMC 10/12AIMEBMTUSAJMO

AMC QuestionCompetition math

One side of an equilateral triangle of height 24 lies on line ℓ. A circle of radius 12 is tangent to line ℓ and is externally tangent to the triangle. The area of the region exterior to the triangle and the circle and bounded by the triangle, the circle, and line ℓ can be written as a√b − cπ, where a, b, and c are positive integers and b is not divisible by the square of any prime. What is a + b + c?

(Copyright of this problem belongs to MAA)

Leaderboards and ratingTry it in the app

Chat with Nova

Meet your new visual AI assistant

Receive 24/7 help from your visual, intuitive, step-by-step tutor that helps you understand any concept.

  • Answers grounded in Stellar lessons
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NovaVisual AI assistantOnline 24/7
Hello, how are you?
Using content from Stellar Lesson
Hello! Welcome to the demo of Nova. You have 6 options of potential questions to choose from. Sign Up for Stellar to ask more questions. How can I help you today?

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What makes Stellar better?

We know how frustrating it can be to find a truly free app, one without ads, subscriptions, or hidden paywalls. That’s why we created a solution, with the best of all your favorite apps, that puts users first.

Features of Stellar compared with Khan Academy, Fiveable, Knowt, Brilliant and AoPS
FeatureStellarKhan AcademyFiveableKnowtBrilliantAoPS
Infinite AI-Powered PracticeIncludedNot offeredNot offeredNot offeredNot offeredNot offered
High Quality Practice QuestionsIncludedIncludedPaid onlyIncludedIncludedIncluded
High Quality Study GuidesIncludedIncludedPaid onlyIncludedIncludedIncluded
Unlimited AP FRQ PracticeIncludedNot offeredPaid onlyPaid onlyNot offeredNot offered
Full-Length AP Practice ExamsIncludedNot offeredNot offeredPaid onlyNot offeredNot offered
Gamification and StreakIncludedIncludedNot offeredIncludedIncludedIncluded
Visual-Based AI AssistantIncludedNot offeredNot offeredNot offeredNot offeredNot offered
Practice from Custom Notes and FlashcardsIncludedNot offeredNot offeredPaid onlyNot offeredNot offered
Interactive Lessons and PracticeIncludedNot offeredNot offeredNot offeredIncludedNot offered
LeaderboardIncludedNot offeredNot offeredNot offeredNot offeredIncluded
Authentic Competitive Math QuestionsIncludedNot offeredNot offeredNot offeredNot offeredIncluded
Intuitive Competitive Math ExplanationsIncludedNot offeredNot offeredNot offeredNot offeredIncluded
Competitive Math Visual TrackerIncludedNot offeredNot offeredNot offeredNot offeredNot offered
Price (per month)Free$0.00$4.00(Khanmigo)$27.00$24.99$27.99≈$40.00(per Book)

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Great free resource

The free aspect of Stellar is great! Hope you don’t decide to change that :)

@burritopig

Looks & works like AP

Love the UI, looks exactly like the AP thing. I love the feature of the 1/4, 1/3 test stuff. Also good.

@dylanh70607

Super helpful & organized

Stellar being free is incredibly helpful and makes it a great resource for lots of students. The layout is simple yet organized. Thank you for putting in the time to make such detailed courses.

@tvisha

Solid AP practice

Good AP Practice Questions

@is_mishra

Easy to navigate

I liked how many courses there are and how easy it is to navigate the app/website.

@evan

Covers important APs

It has a good range of topics and includes important APs and competition questions for free! Really amazing.

@sharkibubble

Clean UI + leaderboard

Easy to understand. I like the leaderboard because it instills some competition.

@emilie

Amazing math competition prep and infinite practice

I'm loving the infinite practice, and the hints. I've always found it difficult to practice for math competitions due to the difficult to navigate websites, but this website puts it all in one place.

@javajellyfish

Feels like real AP material

The wording of the answer choices and questions look a lot like actual AP material.

@alou

Amazing all-in-one platform

I think Stellar is an amazing learning platform. I'm a fan of the active reading section and the mock exam. It's great to have everything completely free, no different tiers. Unlimited analysis and explanation, informative AI. Appearance wise, Stellar thrives.

@coffeecreamer

Aesthetic & works well

It is aesthetic, it works well, it has good questions.

@pengoh_

Amazing UI and courses

The UI is amazing and the courses are perfect, they fit curriculum perfectly for my school.

@newrepublic

This is beyond an app

Stellar is more than an app, it’s a creative escape. I love how beautifully designed it is, how intuitive everything feels, and how it always sparks inspiration. It’s my go to space for ideas and connection.

@zachyhads13

Incredible free resource

I only started using Stellar yesterday evening and I'm absolutely taken aback by how amazing this website is. My favorite part is the variety of AP- Style MCQS- the conceptual ones are perfect for building understanding and the hard AP level questions are perfect for test prep or just for a fun challenge. Thank you so much, I'll definitely being using this website for all my AP classes!

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Super helpful and completly free

I love how it is so helpful and that it is completely free. Stellar gave me confidence when I go into my high school classes! The best part is that it is 100% free!!!!!!!

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Y'all are santa for studying

I love the questions the teaching you even teach AP for free like you guys are like Santa for studying love y'all

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About Stellar

Is Stellar actually free?

Yes, completely. No paywalls, no premium tiers, no hidden fees. Every feature on Stellar, from AI tutoring and mock exams to flashcards and lessons, is 100% free to use. We built Stellar by students, for students, because we believe learning should never be limited by money. Everything here is open to every student, forever.

How does Stellar use AI?

We use AI to scale content, not replace teachers or subject experts. Our AI generates practice questions and explanations on demand, so you never have to wait for new material. We have a team of over 100 student volunteers and verified by educators to ensure quality and accuracy, and review any question that is flagged by our learners. Lessons are written by real experts, not AI, so the experience stays human, reliable, and free.

What does Stellar offer for AP Exams and SATs?

Stellar gives you everything you need to prepare for any AP or SAT exam: unlimited AP-style multiple-choice questions, FRQs, stimulus-based history prompts, and science diagrams. You’ll also find interactive lessons, videos, and full-length Bluebook-style mock exams that look and feel just like the real thing. There’s even an AP Score Calculator for fun. And yes, all of this is completely free.

What does Stellar offer for Competitive Math (AMC, AIME, etc.)?

Stellar includes thousands of past AMC and AIME problems, creating an endless practice experience with detailed explanations. You can track your progress on an interactive problem grid, climb leaderboards, and build your rating through an ELO-based ranking system that feels like a math game. It’s engaging, challenging, and helps you get faster and sharper with every session.

Stellar compared

Stellar vs. Fiveable

Fiveable charges $10 per month and its questions often don’t align with official AP standards, making them unreliable for serious prep. Stellar’s questions are built by students and reviewed by experts to be fully AP-aligned and accurate. Our lessons are interactive, our mock tests are realistic, and every feature is completely free. If you want true AP-style prep, Stellar is the better choice in every way.

Stellar vs. Knowt

Knowt limits access and charges up to $19.99 per month for full features. Stellar gives you unlimited access for free. Our lessons are written and verified by experts, not crowdsourced from random student notes. We also provide complete mock tests, FRQs, and flashcards that align perfectly with AP and IB standards, plus the ability to generate unlimited questions from your own content.

Stellar vs. Quizlet

Quizlet is a solid flashcard app until you hit the paywall. Stellar takes that idea and upgrades it with AI-generated questions, custom notes, and interactive review. Everything you can do in Quizlet, you can do here, but smarter, more adaptive, and free. $0 versus $9.99 per month feels like an easy decision.

Stellar vs. Gizmo

Gizmo offers great free flashcards but covers only a handful of AP subjects. Stellar builds on that same free foundation with 43+ AP courses (and counting), complete with lessons, practice problems, and realistic mock exams. It’s like Gizmo but with everything you need for serious AP and SAT prep: interactive, current, and complete.

Stellar vs. Khan Academy

Khan Academy offers great free videos but covers only a handful of AP subjects. Stellar builds on that same free foundation with 43+ AP courses (and counting), complete with lessons, practice problems, and realistic mock exams. It’s like Khan Academy built specifically for modern high school and college prep: interactive, current, and complete.

Stellar vs. Brilliant

Brilliant is great for conceptual learning, but it doesn’t align with real school curricula or exams. Stellar bridges that gap by combining interactive learning with AP, SAT, and IB accuracy. You’ll master the same engaging lessons, but with material that actually shows up on your tests. It’s practical, results-driven, and completely free.

Stellar vs. AoPS

AoPS offers excellent math problems and books, but they’re expensive and less gamified. Stellar brings that same depth of challenge to everyone for free, with instant feedback, leaderboards, and unlimited problem sets. It’s like AoPS if it were built for every student, not just the ones who can afford it.

Stellar vs. MathDash

MathDash has some useful features, but many are locked behind paywalls and the interface can feel cluttered. Stellar focuses on simplicity, engagement, and performance. Everything is built to help you genuinely improve at AMC and AIME problems. It’s faster, cleaner, and completely free.

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