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 :::{objectives}
 - Understand how collaborative development of lesson material works
+- Understand the design of CodeRefinery lessons
 - Be able to contribute to existing CodeRefinery lessons
 :::
 
 :::{instructor-note}
-- Teaching: ? min
-- Exercises: ? min
+- Teaching: 30 min
+- Exercises: 30 min
 :::
 
 
-Here the episode sections and text ...
+# A look over existing lessons (10min)
+
+## Current Tools Workshop
+
+There is a current list of Tools Workshop lessons on
+[coderefinery.org/lessons](https://coderefinery.org/lessons).
+
+Days 1-3 focus on the practical use of version control. Version control
+is a prerequisite for the somewhat less technical lessons on days 4-6.
+
+One way to understand the structure is that the first 3 days have a
+single **learning objective**: applying the forking workflow to interact
+with open source codes. The second half branches of to multiple useful
+directions.
+
+ * **Days 1-2**: [Introduction to version control](https://coderefinery.github.io/git-intro/)
+ * **Day 3**: [Collaborative distributed version control](https://coderefinery.github.io/git-collaborative/)
+ * **Day 4**: [Reproducible research](https://coderefinery.github.io/reproducible-research/)
+ * **Day 4**: [Social coding and open software](https://coderefinery.github.io/social-coding/)
+ * **Day 5**: [How to document your research software](https://coderefinery.github.io/documentation/)
+ * **Day 5**: [Jupyter notebooks](https://coderefinery.github.io/jupyter/) 
+ * **Day 6**: [Automated testing](https://coderefinery.github.io/testing/)
+ * **Day 6**: [Modular code development type-along](https://coderefinery.github.io/modular-type-along/)
+
+
+## Other lessons
+
+All of our lessons, including main lessons, but also additional lessons for
+other workshops like this one, are on our
+[GitHub page](https://github.com/orgs/coderefinery/repositories). The 
+repositories also contain exercises and workshop pages. All our lessons are
+shared under Creative Commons Attribution, so feel free to use them for your
+own purposes, modify them and make them better.
+
+
+# Backward lesson design (15min)
+
+### Why "Backward"
+
+The "natural" way to design a lesson, that people often default to, is
+to write down material you want to cover and then springle in related
+exercises. This approach has a couple of significant downsides:
+ - The content feel meandering and it's unclear what is meant to be learned.
+ - The exercises and exam may not test the intended learning outcomes.
+
+In backward lesson design we start from the learning objective and the
+"final exam" and work backwards from there to 
+
+### The method:
+
+ 1. Understand you learners
+ 2. brainstorm rough ideas
+ 3. Start from learning objectives. Write down 1-3 overarching learning
+   objectives for the lesson.
+    - think of the things your learners will
+      be able to do at the end of the lesson. Think simple! The simpler
+      the better. Think of three main points they will remember, of which
+      maybe one or two are a concrete skill.
+ 4. Write an summative assesment for each outcome. Try to think of engaging
+    and active exercises.
+ 5. For a longer lesson, add intermediate goals and formative assesments
+    to bridge between the starting point and the learning objective and put them
+    in a reasonable order.
+ 6. Write just enough material to get from one assessment (exercise) to another.
+ 7. Describe the course so the learners know if it is relevant to them.
+
+
+# Contributing (5min)
+
+Our lessons are **collaboratively developed**. They are made by many people, and
+there is no single fixed master plan (but there should be, in the instructors or
+maintainer’s guide). We encourage everyone to contribute to the lessons.
+
+Lessons are reviewed very often - essentially, before each workshop by the
+instructor of that workshop. This can be a quick review, looking at issues and
+fixing easy things, or more thorough.
+
+Every so often (such as at this training), there is an extensive hackathon period of
+fully revising a lesson and making major improvements.
+
+We’ve made the [lesson-review](https://coderefinery.github.io/manuals/lesson-review/)
+checklist to guide the review process.
+
+If you are looking for a quick way to contribute, you can always check issues and
+pull requests on GitHub.
+ - From a lesson page, click "Edit on GitHub" in the top right corner
+ - Click for the "Issues" or "Pull Requests" panel at the top of the page
+ - Comment and take part in the discussion
+
+Some issues you might be able to solve directly. Even then, you should comment on
+the issue first. This way no-one else will start working on it at the same time and
+you can be sure your work will be accepted.
+
+So essentially, we follow the open source collaboration workflow we teach in the
+[collaborative git lesson](https://coderefinery.github.io/git-collaborative/forking-workflow/).
+
+
+# Exercises:
+
+## Lesson design exercise (10-20min, or longer)
+
+ - Pick a lesson topic. Any of the Tools Workshop lessons are OK,
+   or you can choose any other topic you might want to teach.
+ - Write down three learning objectives. What abilities would you
+   expect the student to have at the end of the lesson?
+ - Brainstorm an exercise that demonstrates one of those objectives.
+ - If you have time:
+   - Create two more exercises
+   - Write chapter headers for a quick structure
+
+
+## Contributing exercies (10-20min)
+ 
+ - Read an issue on a CodeRefinery lesson's GitHub page.
+ - Brainstorm solutions. Write a comment in the issue.
 
 
 :::{keypoints}