Passed/Failed: An education in the life of the actor Romola Garai

Romola Garai, 27, had her first leading role in I Capture the Castle. She has since appeared in Atonement, Angel and the BBC1 series Emma. This week she finishes a tour of Three Sisters at the Traverse Theatre, Edinburgh. The DVD of Stephen Poliakoff's Glorious 39 is out on Monday.

There was quite a lot of lying around in fields at Stonar, a small independent girls' school in the country near Bath. It was a non-selective school and the right environment for me: academically not particularly pushy. I did love reading and drama, and my parents took us to a lot of plays. My mother drove me and my sister to private classes in speech and drama with a very gifted teacher, Mrs McEwan, who coached me for the National Youth Theatre. My fall-back position is always to do very little and she made me fill in the forms and post them.

My GCSEs were a mixed bag; I was not the most applied student. I did quite well in English and drama and history, and basically failed my sciences. I left Stonar when I was 16.

I had a very protected, happy childhood – and I was sick of it! I only got into the sixth form of the very selective and academic City of London Girls because it was expanding its drama department and I had got into the National Youth Theatre. My parents let me move up to London and live with my elder sister, who was at the School of Slavonic and East European Studies.

I was taught English particularly well. Miss Rushforth was a fantastic teacher and I was absolutely hooked on the contemporary women poet's course. I had to be specifically asked not to answer every single question in class. But academically I was hopeless:

I'd always try to get a C, maybe a B. Other girls would trot off a brilliant essay and go off to Oxford; I'd think: "Where is the justice?" I took A-levels in English, history and theatre studies and got three Bs.

I was in a school play when a casting director saw me. She was auditioning for The Last of the Blonde Bombshells and I played Judi Dench's character when she was young.

The teaching at Queen Mary, University of London, right in the depths of the East End, was brilliant. I loved it there. Lisa Jardine [the broadcaster and writer] gave the first lecture we had, on Shakespeare – really inspiring.

I was at Queen Mary for a year, then auditioned for I Capture the Castle. I said, "Can I defer my course for a year?" and they said "Yes." I never went back, which is a real shame. I really wanted to finish my degree but I had a mortgage and a career, so I transferred my credits from Queen Mary to the Open University and I did it part-time in four years. I finished my degree last year.

I loved learning by myself. When I was not working, it gave me an objective and a structure to my day. On every job I've done over the last four years, I'd be sat, usually in a crinoline, in a deckchair with a huge book on my lap – a huge source of entertainment to everyone else on the set.

I got a first. I'm going to my graduation ceremony in May and I'm not going to know anyone. When I got my results, it was funny: there was no one to celebrate with, just me at the kitchen table with a glass of wine. I once wrote to one of the teachers saying, "I need extra time for this essay, as we're opening in Lear next week in New York." I asked my tutor if I should mention this production when we studied Lear afterwards and was told: "Probably wise not to foreground that – don't be a knob."