I don't teach the IB syllabus. I reverse-engineer it.
Renzo Diaz is an IB Mathematics and Physics tutor with an M.Sc. in Energy Engineering from Politecnico di Milano, based in Milan and working online with international families worldwide since 2015.
I've spent the last decade teaching IB Mathematics and Physics, working one-to-one with students at international schools in Milan and online. Before that, I trained as an engineer.
That order matters more than it sounds.
I started in 2015, as engineers often do — a side job with flexible hours. What kept me was never the schedule. Within weeks I noticed a structural anomaly: the IB syllabus made sense to me like a system, not a list of topics. I realised I wasn't re-explaining content; I was diagnosing exactly where the student's logic diverged from the mark scheme. That instinct became the method.
To be precise about what's a claim and what's evidence: 2015 is my own account of when I started, and I stand by it — but I'd rather you didn't just take my word for it. The oldest independently dated, public record of this specific practice is my Google Business Profile, publicly accumulating reviews since July 2020. Six years, every one checkable. I hold correspondence from before my public review history — including an exchange from 2016 — that I don't publish, out of respect for student privacy and consent.
One clarification on the word "tutor" in my job title: it's the term people actually search for, so it's the term I use publicly. The real work is closer to what's sometimes called academic performance coaching. AI has commoditised getting the right answer — any model will solve the exercise in front of a student. It hasn't commoditised the confidence to attempt a hard problem without checking if you're right first, the judgement to know which method to reach for, or the discipline to show up to the same weekly slot when it isn't going well. That's the part of the work that doesn't disappear, and it's most of what a session with me actually is now.
Why an engineer, not an education major.
Education
I studied Mechanical and Electrical Engineering at the Universidad Nacional de Ingeniería (Lima), then completed an M.Sc. in Energy Engineering at Politecnico di Milano. I didn't study mathematics to teach it. I studied it to use it — to build systems, model reality, and make decisions where being "approximately right" means something breaks.
Perspective
That is the mindset I translate to your child: maths and physics not as subjects to pass, but as tools to deploy under pressure.
The Diagnostic Engine
Why I can find the gap in minutes, not weeks.
Starting in 2023, I began working with students who had formal diagnoses — autism spectrum, ADHD, 50% extra time — students previous tutors couldn't reach. I could reach them, consistently. To understand why, I underwent a full neuropsychological evaluation at Método Divergentes (Valencia): the WAIS-IV gold-standard assessment. The result: an overall IQ of 139 (top 0.5%), with Working Memory and Processing Speed at the 99th percentile. I don't mention this to impress you. I mention it because it explains the speed of the intervention. When a student explains their confusion, I am not working to keep up. I hold the topic, their attempt, the underlying theory, and the exam constraint in my head simultaneously — and I usually identify the exact failure point before they finish their sentence. That processing speed is not a party trick — it is the same mechanism behind every documented 3-to-7 jump on the results page.
It is the hardware behind the 3-to-7 jump.
A non-negotiable conviction.
I've yet to meet a student who was genuinely bad at maths.
I've met plenty who were convinced of it — usually after years of being taught in a way that was never going to reach them, and concluding the problem was them. That belief is the single most expensive thing a sixteen-year-old can carry into the IB, and taking it apart is often the first real work we do.
If a student isn't understanding, the method hasn't found them yet. That is my burden to carry, not theirs. I have never met a student who was "bad at maths." I have met hundreds who were brutally failed by how it was taught.
The real deliverable isn't the IB grade. It's the operating system.
Nobody solves quadratic equations after they finish school. But the ability to look at a problem you've never seen, map the variables, and execute a logical sequence under time pressure — that is how you survive a hard university degree. The IB syllabus is just the vehicle we use to install that operating system. The grade is just the receipt.
My job is making sure the earning happens as efficiently as possible.
Where I am
I'm based in Milan and work with families at international schools here and across Europe, online. I lead every session personally — there is no team, no associate tutors, no handing your child to someone else. That's the reason I keep the number of students small.
Capacity & Verification
M.Sc. Energy Engineering, Politecnico di Milano (top-tier EU engineering)
Mechanical/Electrical Engineering, Universidad Nacional de Ingeniería, Peru
Cognitive Baseline: WAIS-IV evaluated — IQ 139 (top 0.5%), Processing Speed in the top 1%
Track Record: six years of publicly accumulating Google reviews — 4.9 average, every one a named student
Documented Outcomes: a publicly documented Grade 3 to Grade 7 in IB Math AI SL
Operational: 100% personally delivered. No associate tutors.
Mensa Italia Member: qualifying assessment in the top 2% — independently corroborating the WAIS-IV evaluation above