Passed/Failed: An education in the life of Jonathan Ansell, former lead singer of G4

Jonathan Ansell, 26, was the high tenor in G4, the pop-opera boy band of four students from the Guildhall School of Music & Drama that came second in the ITV talent show The X Factor in 2004, and disbanded last year. His first solo album, Tenor at the Movies, reached No 1 in the classical charts. His next album, Forever, is out in October. He is currently appearing in The Mikado, at Richmond Theatre, Surrey (to 13 September), then at Alexandra Theatre Birmingham (23-27 September). Subsequent tour dates on www.carlrosaopera.co.uk

I was near the bottom of the class at Nyewood Junior School, in Bognor Regis, but really enjoyed music as a release. When I was offered the chance to play the lead in Joseph and the Amazing Technicolor Dreamcoat, the teachers were worried I would lose my focus on the academic subjects, but I was doing something I loved and so became better at them.

The teacher who put me up for the part of Joseph knew the head of the West Sussex Boys Choir, Arthur Robson, and suggested that I audition. I was there for eight-and-a-half years and had an amazing time. For me, school wasn't the best place, but when I went to the choir, I became one of the gang and was the lead soloist at the Royal Festival Hall in a choir competition.

At Bishop Luffa School, an Anglican comprehensive in Chichester, I played rugby, which was thought to be cool, but I was also in the choir, which was completely uncool. After a couple of years, choir rehearsal and rugby practice were on the same night, so I alternated between the two but couldn't really focus on either. So I chose the choir.

Just before GCSEs, I was moved up to the highest set in science, but sadly I got lost in the new syllabus and ended up with a couple of Cs. I failed English language and had to retake it. I loved design & technology, and I've still got the side table I made back then. I dropped physics A-level but carried on with design & technology and music. I got two Ds: in music, I got A for performance but didn't enjoy the academically driven parts – history and interpretation – and it averaged out as a D. When my voice broke at 16, I left the West Sussex Boys Choir with real sadness. I'd had private music lessons for years – from the age of 10, my teacher was Eileen Burrows who, sadly, died when I was 13, a few days after my Grade 8 (as a treble); at least she heard that I'd got it.

Until I was 18, I went to another teacher, Martin Elliot, and got Grade 8 as a tenor. When I was 17, I performed in Littlehampton as a guest soloist with the Arun Choral Society. I sang "Love Changes Everything", and it went down incredibly well. A local MP, Howard Flyte, suggested that I try for the Guildhall School of Music & Drama, and at 18 I got an entrance scholarship.

I had an incredible singing teacher, Adrian Thompson, who was at the top of his game. With a similar voice to mine, he described our lessons as working together; he wasn't dictating to me. I tried my hardest at the academic studies but fell below the standard – I was diagnosed as dyslexic – and at the Guildhall they weren't sure that I should stay, but I managed to convince them and am incredibly grateful.

People used to ask the school for singers: students were cheaper than professionals. G4 was formed as a barbershop quartet but we found the repertoire a bit twee and began to perform "Bohemian Rhapsody" as a four-part harmony, singing the guitar solos as well. We used to busk in Covent Garden. We graduated from the Guildhall in August and were on The X Factor in September. We went to our graduation ceremony and received our diplomas – Associate of the Guildhall School of Music – during the series.

Every now and then, I'm still tempted to do a bit of busking, but I'm not sure the record company would be very happy!