How to Build Claude Skills: Lesson Plan Generator Tutorial

If you use Claude regularly and still retyping the same instructions every single session, you are wasting time you do not have to waste. Build Claude skills once, and Claude remembers exactly how to handle your task every time without you lifting a finger.

Claude Skills, launched by Anthropic in October 2025, is one of the most practical features the platform has ever released. It lets you package your workflow, format rules, and expertise into a simple folder that Claude picks up automatically whenever the task is relevant. No prompts, no repetition, no inconsistency.

In this step-by-step tutorial, you will learn how to build Claude skills from the ground up using a lesson plan generator as your project. By the end, you will have a fully working skill that generates structured, classroom-ready lesson plans in seconds. No coding background required.

Quick Answer

A Claude skill is a folder containing a SKILL.md file with YAML frontmatter and plain English instructions. Create the folder, write the file, upload it to Claude via Settings and Capabilities, and it activates automatically every time your task matches the trigger. That is all there is to it.

What Are Claude Skills and Why Do They Matter in 2026?

Every interaction with Claude starts from a blank slate. There is no memory, no context carried over, and no awareness of how you like things done. For one-off questions that is fine. But for structured, repeatable work like generating lesson plans, writing reports, or formatting documents, starting from scratch every time is a real problem.

Claude Skills solve this entirely. Think of building a skill like writing an onboarding guide for a new assistant. Instead of briefing them every morning on your preferences, you hand them a written guide once. From that point on, they follow it automatically without needing to be reminded.

Here is what makes Claude Skills genuinely different from just saving a long prompt:

• Skills are permanent. A saved prompt still needs to be pasted every session. A skill loads itself automatically in the background the moment it is relevant.
• Skills are consistent. Your wording changes day to day and so does output quality. A skill enforces the same standard every single time without variation.
• Skills work everywhere. The same skill folder works in Claude.ai, Claude Code, and the Anthropic API with no changes needed between environments.
• Skills scale with your team. Since December 2025, admins on Team and Enterprise plans can push approved skills across their entire organisation so every team member benefits automatically.

Here is something most people never realise — Claude has no memory between conversations by default. Every chat is a blank slate. Skills are how you give Claude a permanent brain for your specific workflow.

Do check out HCL-GUVI’s AI ML Zen program if you want to learn how to build real-world AI and machine learning applications; the course offers a structured, mentor-led curriculum covering Python, data science, machine learning, deep learning, and deployment, along with hands-on projects that help you gain practical experience and become job-ready in the AI field.

How Does the Claude Skills System Actually Work?

Before you build Claude skills, it helps to understand the engine running underneath. Claude Skills use a three-level loading system called progressive disclosure, and once you understand it, writing better skills becomes much easier.

The idea is simple. Claude does not load every skill fully into every conversation. That would be slow and wasteful. Instead it works in layers:

• Level 1 — Always loaded: The name and description from your YAML frontmatter. This sits in Claude’s system prompt at all times and tells Claude what skills are available and when to use them.
• Level 2 — Loaded on relevance: The full body of your SKILL.md file. Claude reads this when it decides your skill is relevant to the current task.
• Level 3 — Loaded on demand: Any linked files inside your skill folder, like templates, examples, or reference documents. Claude reads only the files it actually needs for the specific task.

This design means your Claude skills can include as much detail as you need without slowing Claude down. The amount of context bundled into a skill is effectively unbounded because Claude pulls only what it needs.

Think about what this means for a lesson plan generator. You could include different template files for primary school and secondary school, and Claude would automatically load only the one relevant to the grade level you specify.

What Does a Claude Skill Folder Look Like?

A Claude skill is just a folder on your computer. Here is what the full structure looks like for a lesson plan generator:

lesson-plan-generator/ ├── SKILL.md — the required file, the brain of your skill ├── templates/ │ └── lesson_template.md — your output format template └── examples/ *** └── sample_lesson.md*** — a sample output for Claude to benchmark against

The only file Claude skills truly requires is SKILL.md. The templates and examples folders are optional but they make a huge difference to output consistency, especially when you are generating structured documents like lesson plans.

The Two Parts of a SKILL.md File

Every SKILL.md file has exactly two parts. Understanding both before you write anything will save you a lot of trial and error.

The first part is the YAML frontmatter. This sits at the very top of the file between two sets of three dashes. It contains the skill’s name and a description. The description is the most important thing in your entire skill because it is what Claude reads to decide whether to activate the skill or not. A weak description means Claude skills either misses the skill entirely or fires it at the wrong time.

The second part is the instruction body. This is plain English written below the frontmatter. It tells Claude what to do when the skill is active, what format to follow, what sections to include, what tone to use, and how to handle edge cases.

The great news for absolute beginners is that neither part requires any coding knowledge. If you can write a Google Doc, you can build Claude skills.

How to Build Claude Skills: Step-by-Step Lesson Plan Generator

Now let us build the skill. Follow each step in order and you will have a working lesson plan generator skill ready to upload by the end of this section.

1. Create Your Skill Folder

Create a new folder on your desktop. Name it lesson-plan-generator exactly as written, all lowercase, with hyphens between words. Claude Skills folder naming follows strict rules you need to get right from the start:

• Lowercase letters only, no capitals anywhere
• Hyphens between words, never spaces or underscores
• No special characters or numbers at the start
• Never use the words “claude” or “anthropic” in the name, Anthropic has reserved these

Inside the folder, create a new text file. Name it SKILL.md in full uppercase. This capitalisation is case-sensitive, so skill.md or Skill.md will not work.

2. Write the YAML Frontmatter

Open your SKILL.md file and paste the following at the very top. Do not add anything before the first three dashes:

--- name: lesson-plan-generator description: Generates complete, structured lesson plans for educators. Use when the user asks to create a lesson plan, build a class plan, generate teaching material, or plan a lesson for a specific subject, grade level, or topic. ---

When writing your own description for any skill, keep these rules in mind:

• Cover both formal requests like “create a lesson plan” and casual ones like “can you help me plan a science class”
• Include multiple trigger phrases that reflect how real users would ask for the task
• Keep it under 1024 characters
• Never use XML angle brackets inside the description field

3. Write the Instruction Body

Below the closing three dashes of your frontmatter, write the instructions that tell Claude exactly how to generate the lesson plan. This is plain English. Here is the complete body to paste in and customise:

You are an expert curriculum designer with deep experience across all grade levels and subjects. When this skill is active, follow every instruction below without skipping any section.

Step 1 — Collect inputs

Before generating anything, confirm you have all four of the following:

• Subject name (for example, Biology, Mathematics, or History)
• Grade level (for example, Grade 5, Year 9, or Class 11)
• Class duration in minutes
• The specific topic being taught in this lesson

Step 2 — Generate the lesson plan with these five labelled sections

• Learning Objective — one clear sentence stating what students will be able to do by the end of the class. Start it with “By the end of this lesson, students will be able to…”
• Warm-Up Activity — a 5 to 10 minute activity to activate prior knowledge and get the class engaged before the main content begins
• Main Activity — the core teaching segment covering the explanation, examples, student practice, and any group or individual tasks
• Required Materials — a complete list of everything the teacher needs to prepare or gather before the class starts
• Assessment Method — a specific way the teacher will check whether students have understood the lesson, such as an exit ticket, quiz question, or short reflection

Step 3 — Apply these tone and style rules

• Keep language simple, practical, and immediately usable in a real classroom
• Avoid academic jargon and complicated terminology throughout
• Match the vocabulary, activity complexity, and examples to the grade level
• A lesson plan for Grade 3 should feel clearly different from one for Grade 11

Step 4 — Format the output

If a lesson_template.md file exists in the templates folder, use it to format the final output. If no template exists, use clear labelled headings for each of the five sections.

4. Add Your Template File

Inside your lesson-plan-generator/ folder, create a subfolder called templates/ and inside it create a file called lesson_template.md. This template is what gives every lesson plan the same clean structure regardless of subject, grade, or topic.

Paste this into the template file and adjust the layout to match your preferred format:

# Lesson Plan: [TOPIC] Grade: [GRADE] | Subject: [SUBJECT] | Duration: [DURATION] minutes
Learning Objective [OBJECTIVE]
Warm-Up Activity [WARMUP]
Main Activity [MAIN_ACTIVITY]
Materials Needed [MATERIALS]
Assessment [ASSESSMENT]

5. Add an Example Output

Create an examples/ folder inside your skill directory and add one complete, high-quality sample lesson plan. Name it sample_lesson.md.

This step is optional but it makes a real difference. When Claude has an example to benchmark against, it understands your quality standard not just your format. The more detailed and well-written your example is, the more consistent every new plan will be.

What if you added two example files — one for a primary school class and one for a high school class? Claude would automatically calibrate its tone, vocabulary, and activity complexity to match whichever grade level the user inputs. That is the kind of smart, automatic behaviour that makes a skill genuinely powerful.

How Do You Install and Test Your Lesson Plan Generator Skill?

Once your folder is ready, installation takes less than two minutes regardless of which Claude product you use.

1. Installing in Claude.ai

Here is the exact process to get your skill live in Claude.ai:

1. Zip your entire lesson-plan-generator/ folder into a single zip file
2. Open Claude.ai and go to your account Settings in the top right corner
3. Navigate to the Capabilities tab and find the Skills section
4. Upload your zip file, confirm the upload, and save

Your skill is now active across all conversations in your account. Team and Enterprise admins can also push skills organisation-wide from the same settings panel so every colleague gets access automatically.

2. Installing in Claude Code

If you work in Claude Code, the process is even simpler:

1. Move your lesson-plan-generator/ folder into .claude/skills/ inside your project directory
2. Claude Code detects it automatically with no restart needed
3. Live change detection picks up any edits you make to SKILL.md instantly, so you can refine the skill during a session without interrupting your work

3. Testing Your Skill

Open a new chat and type something natural like: “Create a lesson plan on photosynthesis for 10th grade biology, 45 minutes.”

A working skill will produce a fully structured lesson plan with all five labelled sections, following the tone rules and format you set. If the output matches your template and sounds right for the grade level, your skill is ready to use.

If Claude does not trigger the skill at all, here is exactly how to fix it:

1. Go back to your YAML frontmatter description and add more natural trigger phrases
2. Add variations like “lesson outline for”, “teaching plan for”, “class activity on”, and “help me plan a lesson”
3. Re-upload the updated zip file and test again

Tips for Building Better Claude Skills

• Write the description last. Build the full instruction body first. Once you know exactly what the skill does, writing a precise, trigger-rich description is much easier.
• One skill, one job. A lesson plan generator skill should only generate lesson plans. Keep rubric creators, quiz generators, and feedback templates as separate skills. Focused skills trigger more reliably and produce better results.
• Use the examples folder generously. Two or three high-quality sample outputs will improve consistency more than any amount of extra instruction writing. Show Claude the standard, do not just describe it.
• Test with awkward inputs first. Try a 10-minute class, a kindergarten coding lesson, or a mixed-ability group. If the skill handles unusual inputs gracefully, it will handle everything else perfectly.
• Keep every working version. Before editing a skill that is already working well, save a copy. Small changes to the description or instructions can sometimes break trigger behaviour in ways that are hard to trace without a backup.
• Use the skill-creator skill. Anthropic ships an official skill-creator skill that guides you interactively through building new skills. It asks about your workflow, generates the folder structure, writes the frontmatter, and bundles the files you need — no manual editing required.

Conclusion

You now have everything you need to build Claude skills that work. The lesson plan generator you just built is not a demo or an exercise. It is a real, deployable tool that generates polished, classroom-ready lesson plans across any subject, grade level, and duration without you typing a single instruction.

And once you understand the structure, building a new skill takes under 30 minutes. Quiz generators, rubric creators, email templates, student feedback frameworks — every repetitive task that currently lives in your head as a long re-typed prompt can become a skill that runs perfectly without you even thinking about it.

Open a folder, write your SKILL.md, and upload it today. Your future self will thank you every Monday morning.

FAQs

1. Do I need coding experience to build Claude Skills?

Not at all. The core of any skill is a SKILL.md file written in plain English with a few lines of formatting at the top called YAML frontmatter. If you can write a Google Doc, you can build Claude skills. Scripts and executable code are entirely optional extras for advanced automations.

2. What is the difference between a Claude skill and a regular prompt?

A prompt is temporary and disappears when the chat ends. A skill is permanent and loads automatically every time Claude detects the task is relevant. Prompts require effort and produce variable results depending on how you word them each session. Skills are consistent, background-running, and zero-effort after the initial setup.

3. Can I share my lesson plan generator skill with other teachers?

Yes. Zip the lesson-plan-generator/ folder and share it with anyone. They upload it to their Claude account under Settings and Capabilities. Skills are fully portable across accounts and platforms that support the Agent Skills open standard.

4. How many skills can I have installed at the same time?

As many as you need. Claude manages loading through its three-level progressive disclosure system, so only the skills relevant to your current task are pulled into the active context. Having a large library of skills does not slow Claude down or cause conflicts between them.

5. What if Claude keeps ignoring my skill and not triggering it?

This is almost always a description problem in your YAML frontmatter. Add more natural language trigger phrases that reflect how a real user would ask for the task in casual language. The broader and more varied your trigger phrases, the more reliably Claude activates the skill at the right moment.