EXAMS, LANGUAGES & MORE

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62 courses with lessons ready to read

College admission

SAT foundations

Build your reading, grammar, and math foundations with explanations and practice questions.

5 lessons available

TRY A LESSONLesson 1: SAT Fundamentals - Test Structure & Time Management
Spanish

Everyday Spanish for beginners

Start with greetings, then build the words and phrases for family, food, and everyday plans.

5 lessons available

TRY A LESSONLesson 1: Essential Greetings & First Impressions
Application development

.NET developer interviews

Work through .NET development concepts and practise explaining how they work.

3 lessons available

TRY A LESSONLesson 1: Async/Await and Task Parallel Library (TPL) Fundamentals
Explore a course

Anatomy - Bones, muscles, nerves, organs, systems

Read the available lessons in Anatomy - Bones, muscles, nerves, organs, systems and practice what you learn.

5 lessons available

TRY A LESSONLesson 1: Introduction to Human Anatomy
Real estate licensing

California Real Estate Salesperson Exam preparation (CalBRE)

Explore property concepts through the available exam preparation lessons.

5 lessons available

TRY A LESSONProperty Ownership Basics
Chinese · Mandarin

Chinese - Mandarin characters, pinyin, HSK preparation

Get to know Mandarin through characters, pinyin, and HSK preparation.

5 lessons available

TRY A LESSONLesson 1: Basic Greetings and Self-Introduction
Explore a course

Cognitive Biases: Think Clearly, Decide Better

Read the available lessons in Cognitive Biases: Think Clearly, Decide Better and practice what you learn.

8 lessons available

TRY A LESSONLesson 1: Availability & Representativeness โ€” Why We Misjudge Probability
Explore a course

Customs and logistics

Read the available lessons in Customs and logistics and practice what you learn.

4 lessons available

TRY A LESSONLesson 1: Introduction to Customs and Logistics
Dental admission

DAT - Dental Admission Test

Review science and reasoning in the available dental admission lessons.

5 lessons available

TRY A LESSONDAT Fundamentals: Biology & Chemistry Essentials
French

French A1: Your First 500 Words

Your first French words, starting with greetings and introductions.

5 lessons available

TRY A LESSONLesson 1: Essential Greetings and Introductions
Graduate admission

GRE Exam - Practice & Preparation

Explore quantitative and verbal reasoning through the available GRE lessons.

5 lessons available

TRY A LESSONLesson 1: GRE Quantitative Reasoning - Basic Arithmetic & Number Properties
German

German - Cases, vocabulary, common expressions

Make sense of German cases, vocabulary, and everyday expressions.

5 lessons available

TRY A LESSONLesson 1: Introduction to German Cases - The Nominative Case
Version control

Git Mastery โ€” Version Control Without Fear

Get comfortable with version control, one Git concept at a time.

8 lessons available

TRY A LESSONLesson 1: The Git Mental Model โ€” Snapshots, Not Diffs
Japanese

Japanese from Zero: Hiragana to First Conversations

Begin with hiragana and work towards your first conversations.

8 lessons available

TRY A LESSONLesson 1: Hiragana โ€” The Foundation of Japanese
Korean

Korean A1: Your First 500 Words

Start your Korean vocabulary with greetings and introductions.

5 lessons available

TRY A LESSONLesson 1: Greetings and Basic Introductions
Law

MBE (Multistate Bar Exam)

Work through the legal subjects covered in the available MBE lessons.

5 lessons available

TRY A LESSONConstitutional Law and Criminal Law & Procedure
Professional responsibility

MPRE (Multistate Professional Responsibility Exam)

Explore professional responsibility through the available MPRE lessons.

5 lessons available

TRY A LESSONThe Client-Lawyer Relationship
Explore a course

Medical Terminology: Decode Any Medical Word

Read the available lessons in Medical Terminology: Decode Any Medical Word and practice what you learn.

8 lessons available

TRY A LESSONLesson 1: Prefixes โ€” Location and Direction
Pharmacy

NAPLEX (North American Pharmacist Licensure Examination)

Work through pharmacy concepts and calculations, one lesson at a time.

5 lessons available

TRY A LESSONCardiovascular Pharmacotherapy Basics
Practical nursing

NCLEX-PN

Explore the available practical nursing lessons and practise the concepts.

5 lessons available

TRY A LESSONLesson 1: LPN/LVN Scope of Practice & Basic Delegation
Registered nursing

NCLEX-RN (Registered Nurse) licensure exam preparation.

Explore the available registered nursing lessons and practise the concepts.

5 lessons available

TRY A LESSONSafe and Effective Care Environment - Management of Care
Norwegian

Norwegian B1 Level Vocabulary

Expand your Norwegian vocabulary at B1 level, one lesson at a time.

29 lessons available

TRY A LESSONNorwegian B1 Level Vocabulary - Lesson 1
Explore a course

Pathology - Disease processes, symptoms, diagnosis

Read the available lessons in Pathology - Disease processes, symptoms, diagnosis and practice what you learn.

5 lessons available

TRY A LESSONLesson 1: Introduction to Pathology - Understanding Disease
Explore a course

Pharmacology - Drug classes, mechanisms, side effects

Read the available lessons in Pharmacology - Drug classes, mechanisms, side effects and practice what you learn.

5 lessons available

TRY A LESSONLesson 1: Introduction to Pharmacology - Drug Classes, Mechanisms, and Side Effects
Web interfaces

React Hooks

Build your understanding of React through focused lessons and examples.

4 lessons available

TRY A LESSONLesson 1: Introduction to React Hooks
Databases

SQL Fundamentals โ€” Query Any Database

Learn to ask questions of your data with SQL queries.

8 lessons available

TRY A LESSONLesson 1: SELECT Basics โ€” Asking Questions
Legal licensing

U.S. bar exam - Practice & Preparation

Study legal concepts in manageable lessons, then revisit them through practice.

5 lessons available

TRY A LESSONLesson 1: Bar Exam Foundations โ€” Exam Structure and the IRAC Method
Driving theory

UK Driving Theory

Work through driving theory topics in the available lessons.

5 lessons available

TRY A LESSONUK Road Signs and Basic Highway Code Rules
Citizenship

US Citizenship Test

Explore civics topics through the available citizenship test lessons.

5 lessons available

TRY A LESSONLesson 1: Introduction to American Government - The Foundation of U.S. Citizenship
High school equivalency

ged math

Build your foundations with the available GED study lessons.

2 lessons available

TRY A LESSONLesson 1: Working with Whole Numbers - Addition and Subtraction
Programming

Python Programming

Write small Python programs while learning variables, collections, control flow, and functions.

18 lessons available

TRY A LESSONPython Fundamentals
Problem solving

Mastering Leet Code Algorithms

Recognize the patterns behind coding interview problems and practice explaining your solutions.

23 lessons available

TRY A LESSONFoundation: Arrays & Strings
Functional programming

Functional Programming with F#

Use immutable data, functions, and F# types to model problems and build maintainable software.

18 lessons available

TRY A LESSONImmutability & Expressions
Artificial intelligence

2026 Modern AI Search & RAG Roadmap

Explore retrieval, search quality, grounded generation, and the evaluation of practical RAG systems.

38 lessons available

TRY A LESSONFoundations of Modern AI Search
Application development

ASP.NET with .NET 10

Explore ASP.NET Core APIs, request handling, data access, testing, and deployment with .NET 10.

17 lessons available

TRY A LESSONASP.NET Core & Minimal APIs Foundations
Artificial intelligence

Agentic AI as a Part of Software Development

Explore agent workflows, context, evaluation, and the engineering practices needed to use AI in software development.

12 lessons available

TRY A LESSONFoundations of Agentic AI
Secure systems

Authentication & Identity Fundamentals (2026)

Understand authentication, federation, sessions, and authorization through modern identity systems.

5 lessons available

TRY A LESSONIdentity in 2026
Voice applications

Building Real-Time Voice Agents from Scratch

Explore how voice agents listen, respond, and handle interruptions, with attention to latency and audio flow.

8 lessons available

TRY A LESSONPart I: Foundations
.NET development

C# Programming

Build a deeper understanding of C# types, memory, asynchronous code, and modern language features.

35 lessons available

TRY A LESSONC# Fundamentals & Type System
Performance

Cache is King

Reason about cache placement, invalidation, consistency, and the failure modes behind apparently simple speedups.

16 lessons available

TRY A LESSONCaching Fundamentals & Trade-offs
.NET development

Coding Gym Exercises with C#

Explore the available lessons in Coding Gym Exercises with C#. Read at your own pace and practice the concepts along the way.

8 lessons available

TRY A LESSONFoundations: Core Data Structures
Troubleshooting

Debugging Under Pressure

Practice finding useful evidence, narrowing a fault, and choosing recovery actions during production incidents.

21 lessons available

TRY A LESSONThe Moment of Crisis
Developer tooling

Hermetic Builds

Understand reproducible builds, explicit inputs, and the hidden dependencies that make CI results unreliable.

18 lessons available

TRY A LESSONFundamentals of Hermetic Builds
Application development

Java

Explore Java fundamentals, object-oriented design, collections, concurrency, and application development.

14 lessons available

TRY A LESSONJava Fundamentals & Setup
Event streaming

Kafka for .NET Developers 2026

Understand Kafka partitions, offsets, and delivery guarantees, then apply them to reliable .NET consumers.

9 lessons available

TRY A LESSONCore Kafka Mental Model
Artificial intelligence

LLM as Judge: Reproducible Evaluation for LLM Systems

Explore how to evaluate LLM output, recognize judging biases, and combine model judgments with deterministic checks.

10 lessons available

TRY A LESSONWhy Rigorous Eval Exists
Cloud engineering

Mastering AWS

Explore AWS infrastructure, networking, security, reliability, and the trade-offs behind cloud architecture.

27 lessons available

TRY A LESSONAWS Foundations & Core Services
Runtime internals

Mastering Memory Management and Garbage Collection in .NET

Connect .NET garbage collection, allocation, ownership, and pooling to practical memory and performance decisions.

26 lessons available

TRY A LESSONMemory Fundamentals
React data

Mastering Relay

Understand Relay's data model, fragments, mutations, and pagination when building GraphQL applications.

32 lessons available

TRY A LESSONStop Thinking in Queries (Think in Fragments)
Pharmacy

NAPLEX Mastery Roadmap (High-Yield + Weakness-Driven)

Review pharmacy concepts and calculations through the available lessons in this NAPLEX study path.

35 lessons available

TRY A LESSONCalculation Fundamentals & Renal Dosing
Production systems

Production Observability: From Signals to Root Cause (2026)

Connect logs, metrics, and traces to questions about system behavior and the causes of production failures.

21 lessons available

TRY A LESSONObservability Foundations
Web interfaces

React

Build your understanding of React components, state, effects, and data flow through focused lessons.

22 lessons available

TRY A LESSONPrerequisites & Fundamentals
Live applications

Real-Time Web: Streaming, Events, and Live Systems

Compare polling, server-sent events, and WebSockets, then explore the design of reliable live applications.

3 lessons available

TRY A LESSONServer-Sent Events (SSE)
Artificial intelligence

Surviving as a Developer When Most Code Is Generated by AI

Develop the review, debugging, and design skills needed to understand and maintain AI-assisted code.

23 lessons available

TRY A LESSONUnderstanding the AI-Generated Code Reality
Software architecture

System Design Interviews for Software Developers with Examples

Practice reasoning about system design, explaining trade-offs, and working through realistic interview scenarios.

18 lessons available

TRY A LESSONFoundations of System Design
Dental admission

The Dental Admission Test

Review science and reasoning concepts through the available lessons in this Dental Admission Test study path.

7 lessons available

TRY A LESSONFoundation Phase: Core Science Fundamentals
Financial literacy

The Trading Stack

Examine investing and trading concepts, including risk, costs, market structure, and the evaluation of strategies.

9 lessons available

TRY A LESSONTrack 0: The Active Trading Decision
Typed JavaScript

TypeScript

Learn to describe your data with TypeScript and use the type system to make JavaScript code clearer.

19 lessons available

TRY A LESSONTypeScript Foundations
Legal licensing

U.S. Bar Exam

Explore the available legal subject lessons in this bar exam study path and revisit them through practice.

13 lessons available

TRY A LESSONFoundational Legal Principles
Medical licensing

USMLE

Explore the available medical science lessons in this USMLE study path and practice the concepts they cover.

12 lessons available

TRY A LESSONPre-Clinical Foundation
Secure systems

Web Security: The Modern Browser Model

Understand browser security boundaries, cross-origin requests, cookies, and the policies that protect web applications.

25 lessons available

TRY A LESSONBrowser Security Foundations

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