World Languages
8 courses
- AP® Chinese Language & Culture
- AP® French Language & Culture
- AP® German Language & Culture
- AP® Italian Language & Culture
- AP® Japanese Language & Culture
Ace AP®, IB®, SAT®, and Competitive Math with interactive lessons, unlimited practice, flashcards, personalized mock exams, and your own AI tutor. All in one place, and all completely free.
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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.
Open a course, move through the learning loop, and keep every support tool attached to what you are studying.
Every course is one path: lesson, video, practice, exam-style questions and a mastery exam.
What happens to existing bond prices when interest rates rise?
Each step checks your answer straight away and explains why.
Not the main loop, but always nearby when the course needs backup.
Nova, notes, flashcards and progress stay next to what you are studying.
Our lessons designed to help you learn more effectively and efficiently. They are comprehensive, interactive, and make any concept intuitive.
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:
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.
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, 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.
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
Engage with interactive tasks like labeling, problem-solving, and simulations that make complex concepts easier to grasp and retain.
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.
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.
Write Python code to find the nth Fibonacci number.
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.
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.
Trace the Chinese character below.
Click two points, then checkTry it in the app
Access limitless, AI-generated questions that provide continuous practice opportunities, ensuring you’re prepared and confident in every subject.
Multiple Choice Question
What is the effect of an increase in government spending on aggregate demand in the economy?
Select All Question
Which of these happen when government spending increases? Select all that apply.
Short Answer Question
Explain how an increase in government spending affects aggregate demand.
Generated on demandTry it in the app
Prepare thoroughly for all AP® subjects with a variety of mock exams designed to simulate real test conditions.
Consider the curve defined implicitly by
xy2 + ye2x = ln(x) + xy.
Find dydx at the point (1, 1).
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.
“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, 1912The excerpt best illustrates which of the following underlying causes of World War I?
A construction robot is programmed to perform tasks on a building site. The following procedures are defined:
If the robot calls constructStructure(4, 90), which of the following describes its actions?
Voice message
Now you will listen once to a voice message left for a friend.
What kind of confirmation is the speaker asking for?
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?
Bluebook-style exam viewTry it in the app
Master free-response questions (FRQs) with expertly crafted materials designed to mimic AP® exam formats.
Start Learning“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.
The relationship between urbanization and social patterns has significant implications for both human behavior and policy planning.
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) | 0 | 1 | 3 | 5 | 8 |
|---|---|---|---|---|---|
| T(t) (°C) | 15 | 17 | 20 | 23 | 25 |
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 temperatures | Threshold | Output |
|---|---|---|
| [70, 75, 80, 85, 90, 95, 100] | 80 | 4 |
| [60, 65, 70, 75, 80, 85, 90] | 80 | 3 |
| [0, -5, -10, -15, -20, -25, -30] | -10 | 2 |
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.countDaysAboveThreshold method. It iterates through the dailyTemperatures array, counts how many days have temperatures above the provided threshold, and returns the count.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:
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.
Start LearningContests AMC 10/12AIMEBMTUSAJMO
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?
Leaderboards and ratingTry it in the app
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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.
| Feature | Khan Academy | Fiveable | Knowt | Brilliant | AoPS | |
|---|---|---|---|---|---|---|
| Infinite AI-Powered Practice | Included | Not offered | Not offered | Not offered | Not offered | Not offered |
| High Quality Practice Questions | Included | Included | Paid only | Included | Included | Included |
| High Quality Study Guides | Included | Included | Paid only | Included | Included | Included |
| Unlimited AP FRQ Practice | Included | Not offered | Paid only | Paid only | Not offered | Not offered |
| Full-Length AP Practice Exams | Included | Not offered | Not offered | Paid only | Not offered | Not offered |
| Gamification and Streak | Included | Included | Not offered | Included | Included | Included |
| Visual-Based AI Assistant | Included | Not offered | Not offered | Not offered | Not offered | Not offered |
| Practice from Custom Notes and Flashcards | Included | Not offered | Not offered | Paid only | Not offered | Not offered |
| Interactive Lessons and Practice | Included | Not offered | Not offered | Not offered | Included | Not offered |
| Leaderboard | Included | Not offered | Not offered | Not offered | Not offered | Included |
| Authentic Competitive Math Questions | Included | Not offered | Not offered | Not offered | Not offered | Included |
| Intuitive Competitive Math Explanations | Included | Not offered | Not offered | Not offered | Not offered | Included |
| Competitive Math Visual Tracker | Included | Not offered | Not offered | Not offered | Not offered | Not offered |
| Price (per month) | Free$0.00 | $4.00(Khanmigo) | $27.00 | $24.99 | $27.99 | ≈$40.00(per Book) |
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I was completely overwhelmed with my APs at first. I didn’t have the motivation to study or the right resources to succeed. But Stellar changed everything. Its immersive experience kept me motivated, and the high-quality study guides, practice problems, and mock tests gave me the tools I needed. And it’s completely free too!
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The free aspect of Stellar is great! Hope you don’t decide to change that :)
Love the UI, looks exactly like the AP thing. I love the feature of the 1/4, 1/3 test stuff. Also good.
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.
Good AP Practice Questions
I liked how many courses there are and how easy it is to navigate the app/website.
It has a good range of topics and includes important APs and competition questions for free! Really amazing.
Easy to understand. I like the leaderboard because it instills some competition.
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.
The wording of the answer choices and questions look a lot like actual AP material.
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.
It is aesthetic, it works well, it has good questions.
The UI is amazing and the courses are perfect, they fit curriculum perfectly for my school.
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.
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!
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!!!!!!!
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
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.
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.
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.
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
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.
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.
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.
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.
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.
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.
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.
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.
Probably the only study site you'll see all day with zero paywalls. Other "free" study sites hate us for this one.