How I'm Teaching the New IBDP Biology Syllabus (first Exam May 2025)
It's been about 2 months, 6 subtopics and 1 unit test since I started teaching the new IBDP Biology course and now that I've been through it a bit I feel more confident about sharing my plans with the wider community of IBDP Biology teachers out there. It is important to note that at my current school in Morocco I teach a mix class of SL & HL students, so I need to plan my SL release times so that they are fairly evenly spread throughout the units. It should also be noted that we have students at a wide variety of levels and many are non native-English speakers. These factors all came into play as I decided upon this sequence for my first time through the new syllabus.
Year 1:
Unit 1: Evolution & Biodiversity (22 hours)
A2.3 Viruses (HL only)
A3.1 Diversity of organisms
A3.2 Classification & cladistics (HL only)
A4.1 Evolution & speciation
B4.1 Adaptation to environment
D4.1 Natural selection
Unit 2: Cell Biology (24 hours)
A2.1 Origins of cells (HL only)
A2.2 Cell structure
B2.1 Membranes & membrane transport
B2.3 Cell specialization
D2.1 Cell & nuclear division
Unit 3: Biochemistry & Molecular Biology (25 hours)
A1.1 Water
B1.1 Carbohydrates & lipids
B1.2 Proteins
C1.1 Enzymes & metabolism
C1.2 Cell respiration
D2.3 Water potential
Unit 4: Physiology (38 hours)
B3.1 Gas exchange
B3.2 Transport
B3.3 Muscle & motility (HL only)
C2.1 Chemical signalling (HL only)
C2.2 Neural signalling
C3.1 Integration of Body systems
C3.2 Defence against disease
D3.3 Homeostasis
Unit 5: Experimental Design for Biology & the IA
Ethics & experimental design
Ensuring reliability & validity
Collecting & processing data
Statistics
Mock IA
Real IA proposal & work time (about 9 of the 10 required hours if possible)
Collaborative Sciences Project
With Chemistry, Physics & ESS students
Field work after final exams in June
Year 2:
Unit 5: Experimental Design for Biology & the IA continued
IA commentary feedback
Peer editing with checklist
Upload to IBO
Unit 6: Ecology & the Environment (33 hours)
A4.2 Conservation of Biodiversity
B4.2 Ecological niches
C1.3 Photosynthesis
C4.1 Populations & communities
C4.2 Transfer of energy & matter
D4.2 Stability & change
D4.3 Climate change
Unit 7: Heredity (39 hours)
A1.2 Nucleic acids
D1.1 DNA replication
D1.2 Protein synthesis
D1.3 Mutations & gene editing
D2.2 Gene expression (HL only)
D3.1 Reproduction
D3.2 Inheritance
Unit 8: Exam Review
Past paper questions
Mini-mocks (real mocks are in January)
While working my way through the new syllabus I debated several different approaches, including teaching it in the order of the Subject Guide (which is what I did the very first time I taught the current syllabus), but I decided to stick with what I know works in terms of general themes and topics. I have found that starting big with Biodiversity & Evolution really prepares students with context and examples for the other topics in the course. I then zoom in to the cellular level, then further in to the molecular biology level & finally move to apply that knowledge while studying physiology. I like to do Genetics last as students tend to forget that one and it's connections to the other units are more obvious and start Year 2 with Ecology (in which I include photosynthesis to keep it separate from Cellular Respiration to avoid confusion & remind students of similarities and differences in Year 2).
I developed several different unit and topic sequences besides the one shared above, which I have chosen to go with this time around... I also have a calculation method that I use to figure out how many classes to spend on each topic, if these planning tools interest you, you can find them in my TPT shop soon (this week, I promise!).
Stay tuned for a future blog post at the end of this school year & next year as I reflect on this particular unit sequence to see if I stick with it or not. So far, I am quite happy with the way the topics in Unit 1 spiraled and reinforced each other, hopefully this trend continues in the next few units.
Thanks for reading teachers, travelers and curious souls of all kinds.
The Roaming Scientist





Thank you for this! I am a new bio teacher this year (DP1 only) and paniking! You resources are starting to shed some light and clarity for me...hope to be in touch more.
I enjoyed reading this because airport transportation is often overlooked when planning a trip. Searching for an airport taxi near me in Anaheim, California can help travelers find a convenient option when they need transportation at a suitable time.