EXAMS, LANGUAGES & MORE

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64 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
Exam preparation

Norsk Exam Prep

Read the available lessons in Norsk Exam Prep and practice what you learn.

5 lessons available

TRY A LESSONLesson 1: Expressing Opinions, Preferences, and Priorities in Norwegian
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.

36 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.

10 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.

31 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
Cloud engineering

Terraform for AWS Backends

Explore the available lessons in Terraform for AWS Backends. Read at your own pace and practice the concepts along the way.

7 lessons available

TRY A LESSONStart Here: What Terraform Is
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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