IB CAS: Activities, Outcomes & Reflection
"What am I actually meant to do for CAS?" and "I can't write these reflections" — here's a clear walkthrough of CAS, which is ungraded yet required, from choosing activities to reflecting well.
CAS is one of the three core requirements of the IB Diploma, made up of three strands — Creativity, Activity and Service. It sits alongside Theory of Knowledge (TOK) and the Extended Essay (EE), yet because it isn't graded it's the one students most often put off. The catch: it's required to be awarded the diploma. Here's how to work through it, from choosing activities to writing reflections that actually land.
What is CAS? (Not graded, but required)
The defining feature of CAS is that it isn't assessed with marks or grades — there's no "7" the way there is for a subject. That doesn't make it optional, though: if you don't meet the CAS requirements, the diploma can be withheld. You can have the subject points you need and still not be awarded the diploma if CAS is incomplete.
The three strands break down roughly like this:
- Creativity — arts, music, design and creative thinking; anything involving original, creative engagement.
- Activity — sport, training, hiking and other physical exertion.
- Service — contributing to others or your community. Not one-way "helping," but responding to a genuine need.
CAS isn't a log of what you did — it's about what you learned through doing it. How you engaged and what changed in you matters far more than how impressive the activity looks.
The seven learning outcomes
Across your CAS programme, you're expected to demonstrate the seven CAS learning outcomes. At a high level, these cover roughly the following (always check the IB CAS guide for the exact wording):
- Identifying your own strengths and areas for growth
- Undertaking new challenges and developing new skills
- Planning and initiating activities yourself
- Working collaboratively with others
- Showing perseverance and commitment
- Engaging with issues of global significance
- Considering the ethical implications of your actions
The important thing: no single activity has to tick every box. The idea is that these are demonstrated across your CAS programme as a whole — the accumulation of your various experiences — rather than all at once.
How the CAS project works
Separate from your individual experiences, CAS includes a CAS project — a collaborative undertaking.
- Planned and carried out with others
- Typically lasting at least one month
- Can involve one or more of Creativity, Activity and Service
The aim is to experience the full plan → act → reflect cycle as a team. Revising your plan partway through, or navigating disagreements over who does what, is itself part of the learning. Follow your school's or coordinator's guidance on length, format and what you submit.
Reflection: quality over quantity
A common misconception is that writing more earns you more credit. In reality, quality — depth and insight — is what matters.
Good reflection answers questions like these in your own words:
| Lens | Ask yourself |
|---|---|
| Feeling | What did this experience make me feel? |
| Learning | What did I learn, and which skills grew? |
| Challenge | What didn't go well, or felt difficult? |
| Next | How will I use this, and what will I change? |
Reflection doesn't have to be written prose — it can be combined with evidence like photos, video or audio. What matters isn't what you did but that how you changed through the experience comes across.
How to do CAS well
To finish, a few habits that make CAS go smoothly:
- Balance C / A / S. Look at the whole picture early so you don't lean too heavily on one strand.
- Reflect for real. Don't stop at "it was fun" — write down the insight and your next step.
- Collect evidence as you go. Gathering photos and notes after each activity hugely reduces the end-of-term scramble.
- Start early. The more you cram before the deadline, the more you lose the real value of CAS — learning from experience. Sort out your time management early so CAS runs alongside your subjects rather than competing with them.
The biggest waste in CAS is treating it as a box-ticking exercise and finishing it in form only. When you can genuinely put your growth into words, those experiences become a real asset for your university essays and interviews too — and free up room in your overall score strategy. If you're unsure how to approach it or how to write your reflections, a conversation with an IB graduate who's been through CAS can shift how you see the whole thing.