"I was getting into trouble because I had nothing to do all day," he said. "The course actually gave me something to focus my mind on."
Mark heard about the course from his probation officer and was amazed by the easy atmosphere he found at the college when he turned up for the programme. "Everyone's on first name terms and it's very relaxed.
"I messed about at school and I thought this would be the same old thing, but it's really new and interesting and now I want to get more qualifications and earn some money."
His only problem with the college is one that many of the students have discovered. It teaches basic, rather than advanced, IT. After just a few weeks on the course, teachers are predicting that some of the boys will have finished it by Christmas.
"Sometimes they have to send us home early because there's not enough work for us," said Chris Richards, 18, who joined the programme after hearing about it from Churches Housing, a housing association in Luton. The question is what will they do for the rest of the year?
Having turned them on to education for the first time in their lives, Dunstable College has no intention of losing its students at this stage. European officer Nicola Healey said: "Some are very quick and able and are clearly going to finish the course early. We have already identified further courses we can put them on, including a desktop publishing course."
Chris heard about the course after his parents threw him out. He needed to find a programme to follow during the day in order to qualify for his own council flat. Now, however, he has dreams of taking an advanced programming course and earning mountains of money in a high-powered job.
The group have already learned how to produce business cards and letter heads in a range of fonts and styles. They have picked up graphics packages such as Quark and got to grips with spreadsheets.
The course has also helped Chris's relationship with his parents, who are now keen to talk about and help him with what he is learning. "I found school boring and too much of a long day, so I left at 16. But this is different, " he said.