Nearly half a million children a week gamble and 9,000 are problem gamblers, according to a study by the industry regulator.

The Gambling Commission’s Young People and Gambling report(pdf) found that while rates of smoking, drinking and drug-taking among children have declined, gambling rates have remained largely static, with 450,000 11- to 15-year-olds involved in the activity each week.

The most popular way to gamble among children was on fruit machines in pubs or arcades, followed by private bets with friends and card games. But the survey also found that children were attracted to gambling-style games that replicate real forms of betting.

Of the children who said they had played a gambling-style game, poker was the most popular, and smartphone apps and Facebook were the most likely platforms used to play.

The overall rate of gambling among 11- to 15-year-olds in England and Wales was 16%, twice the proportion who drink alcohol, the next most popular vice among children.

Nearly 60% of children surveyed acknowledged that gambling was dangerous but 24% said they did it anyway “to make money”, while 23% said it was fun and 21% said it was exciting.

Tim Miller, the commission’s executive director, said: “We’re often reminded to discuss the risks of drinking, drugs and smoking with our children. However, our research shows that children are twice as likely to gamble than do any of those things.

“We want to reassure parents that our rules require gambling businesses to prevent and tackle underage gambling and we take firm action where young people are not properly protected.”

The commission found that boys were twice as likely as girls to bet, with 21% of boys surveyed admitting they had gambled in the week leading up to the study, compared with 11% of girls.

Three-quarters of them had seen gambling advertisements on television, and nearly two-thirds had been exposed to betting ads on social mediaAlmost one in 10 said they following a gambling company on sites such as Facebook or YouTube.

The government recently signalled its intent to examine gambling adverts during daytime TV, when they are permitted as long as they accompany sporting events. Gambling companies’ TV ad spend has more than doubled since 2012 and has reached £162m already this year, the Guardian revealed last month.

But the commission said there was little evidence that advertising was inducing children to bet. Instead, it pointed to factors such as the habits of parents making gambling seem like a “banal” activity.

“The key social risk that increases the likelihood of problem gambling in the future is having parents who introduce their children to gambling at an early age or having parents who are heavy gamblers themselves,” said the commission.

It added: “Fathers are less likely to discuss problem gambling behaviour or view underage gambling as a serious issue.”

Despite concern about the prevalence of gambling among children, the commission said just 0.4% of children could be classed as “problem gamblers”, and a further 1.6% could be deemed “at risk”.

The Labour MP Carolyn Harris, who chairs a cross-party parliamentary group on fixed-odds betting terminals (FOBTs), said: “It is very concerning that any children are categorised as ‘problem gamblers’ and I would urge the government and Gambling Commission to undertake further research in this area and for industry to take every step possible to protect the young and vulnerable.”

GamCare, which provides support to problem gamblers, said it had set up youth hubs in UK cities to educate children and provide tools to help teachers and youth services identify children at risk. It also runs a gambling awareness website aimed at children.

Bookmakers are going to greater lengths to prevent children from placing bets, according to a “mystery visitor” test of their adherence to the Think 21 campaign, which demands that they challenge anyone who looks under 21.

In 2014, 70% of mystery visitors aged 18 and 19 were challenged before they placed a bet. In the first half of 2016 the proportion rose to 78%.