UK teenagers are less happy with their lives than those in many other nations, with girls much less satisfied than their male classmates, an international report has found.
It reveals that the nation is lagging behind other countries including the US, Germany and Latvia when it comes to young people's social and emotional lives.
As well as being less satisfied with life, the UK's teenagers are more likely to face exam anxiety and bullying than many of their peers, an international report has found.
And there is a major gender gap, with girls more likely to worry about their exams, according to the latest report by the Organisation for Economic Co-operation and Development (OECD).
The study - based on the OECD's Programme for International Student Assessment (Pisa) tests, which are taken by 15-year-olds around the world - found that, on a scale of one to 10, British pupils had an average satisfaction of 6.98, compared with the OECD average of 7.31.
This puts the UK behind nations such as France (7.63), Germany (7.35), Spain (7.42), Latvia (7.37) and the US (7.36), but ahead of others such as Japan (6.80), Turkey (6.12) and Korea (6.36).
Among those with the highest ratings were Mexico (8.27) and Finland (7.89).
Overall, the UK took 38th place for life satisfaction, out of 48 OECD countries, and partner nations. Among OECD countries alone, it was 23rd out of 28.
UK boys had an average score of 7.31, compared to 6.64 for UK girls - a gap larger than the OECD average.
This is a bigger gap than in 17 other countries, and only ahead of Turkey, Greece, Korea and Italy within the OECD nations.
In Japan alone, girls had higher life satisfaction than boys.
Gabriela Ramos, OECD chief of staff, said that the report showed some "worrisome" results for gender that need to be tackled.
"Again, we confirm, and this is evidence, that girls report lower levels of satisfaction, that they are subject to a lot of pressures, from social media, that they are less happy with themselves," she said.
The report notes: "Pisa 2015 does not collect data on students' body image, but other research suggests that exposure to images of overly thin girls and young women in traditional media and to photo-sharing in new social media has a significant negative impact on adolescent girls' satisfaction with themselves."
Around 540,000 students took part in the latest Pisa tests, representing around 29 million 15-year-olds in 72 participating countries and economies.
The findings show that British pupils' time at schools is more regularly marred by bullying, with almost a quarter of British students (24%) having fallen victim to any type of it, compared to 19% across OECD nations and economies.
Anxiety was also found to be permeating the British classroom, where 72% of students reported worrying about tests even if they were well-prepared, compared with 55% on average.
Again, a gender breakdown shows that three quarters (76.3%) of UK girls say they worry about getting poor grades, compared to 58.6% of their male class mates.
Girls were also more likely to say they feel very anxious before a test and get tense when they study.
Ms Ramosa said: "Across the OECD countries, students that reported the highest levels of anxiety also recorded a low level of life satisfaction."
She noted "I think the UK is one of the champions in terms of putting a lot of pressure on for tests", adding that this increases anxiety.
The reported lack of happiness teenagers have in British schools is offset by their high ambitions, the report found.
The vast majority of pupils (90%) claimed they wanted to be the best in their every endeavour, dwarfing the 65% international average, while 76% said they wanted to be the best in their class, compared to the 59% OECD average.
UK teenagers also have a high level of support from their parents, with 93% saying that their mothers and fathers encourage them to be confident, and 84% saying their parents are interested in what they do at school.
Barnardo's chief executive Javed Khan said: "These findings highlight just how vital it is for children to have someone who believes in them.
"A caring home is essential to children's wellbeing and children themselves have told us that having someone to love, listen to, support and trust them is vital for them to lead happy lives."