SOLO taxonomy, or the Structure of Observed Learning Outcomes, is a five-level framework for understanding how student thinking develops, from surface recall to deep, transferable knowledge. Developed by John Biggs and Kevin Collis in 1982, it gives teachers a practical way to design tasks, read student responses, and give feedback that actually moves learning forward.
Key Takeaways
- SOLO taxonomy has five levels: pre-structural, uni-structural, multi-structural, relational, and extended abstract.
- It was developed by John Biggs and Kevin Collis and first published in Evaluating the Quality of Learning (1982).
- It works across every subject and year level and not just written tasks.
- The most useful shift for teachers is designing questions and tasks that target relational and extended abstract thinking, not just recall.
- Common mistake: using SOLO as a grading tool. It works best as a formative guide.
SOLO Taxonomy categorises learning outcomes and guides teaching strategies and can transform assessment practices to better support student growth.
What are the Five Levels of SOLO Taxonomy
Your students don’t all arrive at the same place. What SOLO taxonomy gives you is a way to see exactly where each of them is, and what the next step looks like, without adding a new system to your already full plate. SOLO Taxonomy consists of five distinct levels that illustrate the progression of student understanding. Each level represents a different depth of learning, from basic recall to complex synthesis of ideas.
The five levels move from fragmented understanding through to original, creative thinking:
1. Pre-structural Level
The pre-structural level is characterised by a lack of understanding. At this stage, students may have fragmented knowledge or misconceptions about a topic.
A student at this level has picked up fragments, but often incorrect ones. They can repeat a word or phrase without understanding what it means or why it matters. In a Year 9 History class, this might look like a student who knows a war “had something to do with archduke something” but can’t place it, sequence it, or connect it to anything else. Teachers need to provide targeted interventions and support to help these students move beyond this initial stage of learning.
2. Uni-structural Level
At the uni-structural level, students one relevant idea. They can define a term, recall a fact, or perform a single step, but they’re not yet connecting it to anything else. They struggle to see the broader implications or relationships between ideas. For example, a student may understand the definition of a scientific term but may not be able to apply it in a practical context or relate it to other concepts within the subject.
To support students at this level, you can encourage them to explore connections between ideas and provide opportunities for them to practise applying their knowledge in different scenarios. You could use guided discussions, hands-on activities, and collaborative learning experiences to promote deeper engagement.
3. Multi-structural Level
Here, students can identify several relevant ideas but haven’t yet connected them into a coherent picture. There is a growing awareness of the complexity of the subject matter. For instance, a student might be able to list the components of a cell and describe their functions but may struggle to explain how these components work together to support the overall function of the cell. To help students progress and develop a more integrated understanding, you can encourage them to share insights and challenge each other’s critical thinking through activities such as concept mapping or group projects that require collaboration and discussion.
4. Relational Level
At the relational level, students begin to connect and integrate different aspects of their knowledge. This is where deeper thinking begins. Students start linking ideas, seeing cause and effect, comparing across contexts. A Year 10 Science student at this level doesn’t just know what photosynthesis is, they can explain why it matters for a particular ecosystem and predict what happens when one variable changes.
5. Extended Abstract Level
The highest level of SOLO Taxonomy. Here, students demonstrate the ability to generalise their knowledge and apply it creatively in novel contexts.
Students take their understanding beyond the given context. They are generating new ideas, making cross-disciplinary connections, or applying a concept in a way they weren’t taught. This is harder to plan for, but it’s worth building tasks that make it possible.
These five levels aren’t a ladder students climb once. They move up and down depending on the topic, the task, and how new the material is.
How Do You Use SOLO Taxonomy in the Classroom?
By utilising the taxonomy as a framework for lesson planning, you can ensure instruction is purposeful and focused on promoting deeper learning. The most practical entry point is task and question design.
For example, if every question you ask sits at the uni-structural level — recall, define, list — your students will stay there. SOLO gives you a map for deliberately building in relational and extended abstract thinking.
A few approaches that work:
- Tiered tasks. Write the same task at three SOLO levels so students can access it at their current point and stretch upward. Year 8 Geography: describe one effect of deforestation (uni-structural) → explain how deforestation affects multiple environmental systems (relational) → evaluate a government policy response and propose an alternative (extended abstract).
- SOLO-coded rubrics. Share the five levels with students in plain language so they can self-assess before submitting their work. This builds the metacognition that makes the taxonomy useful over time. In practice, that means translating the level names into student-facing language: not “extended abstract” but “I can take this idea and apply it somewhere we haven’t studied.”
A Year 10 English rubric for an analytical essay might read:
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- Pre-structural: I’ve written about the text but I’m not sure what my argument is.
- Uni-structural: I’ve made one point about the author’s technique.
- Multi-structural: I’ve identified several techniques but haven’t connected them.
- Relational: I’ve explained how the techniques work together to create a specific effect.
- Extended abstract: I’ve connected the author’s choices to a broader idea about how language shapes meaning, and I’ve done that in my own way, not just repeated what we covered in class.
Students who can place themselves accurately on that scale before they submit their work are far more likely to revise with purpose and reflect on their own learning rather than just reading their work back to themselves.
- Feedback anchored to the levels. Student feedback should be specific and constructive. Instead of “good work, add more detail,” try “your response is at the multi-structural level because you’ve listed three causes. Can you explain the relationship between them?” That’s a direction, not just a grade.
All three of the approaches mentioned above work best when you’re reading student responses through a SOLO lens regularly, not just at assessment time. Formative assessments — exit tickets, quick writes, class discussions — are well-suited to that kind of SOLO-level reading. You don’t need to score every response; you need enough of a signal to know where to take the class next..
What Are The Benefits of SOLO Taxonomy for Teachers?
The clearest benefit is precision. SOLO gives you a common language for talking about the quality of thinking, not just whether an answer is right or wrong. That’s useful in feedback conversations, in planning, and in department moderation. It also works across subjects. Unlike some frameworks that sit more comfortably in English or Humanities, SOLO applies equally well in Maths, Science, Languages, and English. The levels describe how thinking develops, not what thinking looks like in a specific discipline.
How Can SOLO Taxonomy Help Learners?
For students, the benefit is clarity. When they know what a relational response looks like as opposed to a multi-structural one, they have a target, not just a vague instruction to “go deeper.” By clearly defining learning objectives and outcomes, SOLO Taxonomy helps students understand what is expected of them. This clarity can lead to improved academic performance and a more engaging learning experience.
SOLO Taxonomy has the potential to cultivate a culture of lifelong learning. By emphasising the importance of deep understanding and critical thinking, you can inspire students to become curious, self-motivated learners who seek knowledge beyond the classroom; a mindset is essential in today’s rapidly changing world, where the ability to adapt and learn continuously is crucial for success.
What Are Common Mistakes When Using SOLO Taxonomy?
- Using it as a grading tool. SOLO describes a quality of thinking, not a grade. A pre-structural response on a genuinely difficult task might come from a strong student encountering new material. Read it diagnostically, not judgementally.
- Confusing SOLO with Bloom’s taxonomy. Both describe levels of thinking, but they’re built differently. Bloom’s is a hierarchy of cognitive skills (remember, understand, apply, analyse, evaluate, create). SOLO describes the structural complexity of a response. They’re complementary, not interchangeable.
- Applying it only to written tasks. SOLO works in discussion, in practical tasks, in oral assessment. A student explaining their maths reasoning aloud can be at any SOLO level: you don’t need a written response to use the framework.
- Skipping the relational level. It’s tempting to jump from multi-structural tasks straight to extended abstract. The relational level, where students learn to connect and integrate, is where the real consolidation happens. Don’t rush past it.
Frequently Asked Questions
Who developed SOLO taxonomy?
SOLO taxonomy was developed by John Biggs and Kevin Collis and first published in Evaluating the Quality of Learning: The SOLO Taxonomy (1982). Biggs, an Australian educational psychologist, designed it as a practical tool for assessing the quality of student responses rather than the quantity of information recalled.
How is SOLO taxonomy different from Bloom’s taxonomy?
Bloom’s taxonomy classifies types of cognitive skill, from remembering through to creating. SOLO taxonomy describes the structural complexity of a student’s response to a specific task. Both are useful; they answer different questions. Bloom’s asks “what kind of thinking?” SOLO asks “how well-developed is this thinking?”
What year levels is SOLO taxonomy suitable for?
SOLO taxonomy works across Years 7–12 but can be adapted for lower levels. The language used to describe the levels needs to change with the age group, but the underlying framework applies wherever you’re assessing the quality of student thinking.
Can SOLO taxonomy be used for self-assessment?
Yes, and it’s one of its strongest applications. When students can identify their own SOLO level, they develop metacognitive awareness that transfers across subjects. Try sharing the five levels in plain language, give students a model response at each level, and build self-assessment into your task design.
Does SOLO taxonomy work in subjects other than English and Humanities?
Yes. The framework describes cognitive structure, not subject content, so it applies equally in Maths and Science, as demonstrated by the examples given in this blog. A Year 11 Chemistry student explaining reaction mechanisms can be at a multi-structural or relational level regardless of subject.
How do you introduce SOLO taxonomy to students?
Start with a familiar topic they already know well, such as sport, a recent film, something outside the curriculum. Show them what a pre-structural, multi-structural, and relational response looks like on that topic. Once they understand the levels in a low-stakes context, apply it to classroom content.
SOLO Taxonomy Summary
SOLO Taxonomy is a valuable pedagogical tool for educators seeking to enhance their teaching practices and improve student learning outcomes. It won’t change what you teach, but it will sharpen how you see what your students are doing with it.
The framework gives you a common language for the quality of thinking, a practical lens for reading responses, and a clear direction for the feedback you give. You can create a more effective and engaging learning environment that supports the diverse needs of your students.
Used well, SOLO Taxonomy makes the difference between a class that’s busy and a class that’s actually moving forward.
References
Biggs, J., & Collis, K. (1982). Evaluating the Quality of Learning: The SOLO Taxonomy. Academic Press.
Hook, P., & Mills, J. (2011). SOLO Taxonomy: A Guide for Schools. Essential Resources Educational Publishers.
About the author
Rachel Ellis, MA Applied, is a content writer at Education Perfect, with 20 years’ experience in edtech and a background in English teaching. She writes about pedagogy, assessment, and classroom practice for teachers across Australia and New Zealand.
