A project that works with young people to boost self-esteem says its services are "needed now more than ever".
Revealed Projects provides workshops in schools and youth clubs on wellbeing and healthy relationships for nine to 18-year-olds across north Somerset.
Manager Adele Sutton said: "Young people are struggling, in particular as a result of the pandemic."
Following a session, one primary school pupil said she felt like she "was worth more" and was "valued".
"We are seeing schools inquiring more about our services, asking if we can come in and come in straight away," Ms Sutton added.
"On a national scale there has been research that shows young people have had real issues with anxiety, social isolation and feeling a lot more lonely."
Ms Sutton's first group workshop following the return of children to school was at Uphill Village Academy in Weston-super-Mare, where she worked with four different classes.
Year 5 pupil Eden said: "After the workshop it made me feel that I'm not the only one who looks at things in a different way. I felt I wasn't alone in the things that I feel and the things that I do."
Amelia added: "Afterwards I felt much happier and comfortable with my thoughts and emotions and about how people perceived me."
The project, which was launched by Holy Trinity Church in Weston-super-Mare in 2016, has worked with more than 1,800 young people across 31 agencies, including primary and secondary schools, pupil referral units and youth groups.
It also provides parent and carer workshops and small targeted sessions.
The not-for-profit project is now looking for 1,000 people to donate £1 a week to help it continue to provide the service.
The Mental Health of Children and Young People in England 2020 report, which is produced by NHS Digital and the Office for National Statistics, is the official stock-take of the state of children's wellbeing.
It has been tracking more than 3,000 young people over the past four years.
Its latest findings, published in the autumn, found one in six children aged five to 16 had a probable mental health disorder, up from one in nine three years previously.
Head teacher Samantha Hodder said mental health was "massively" important and that schools must talk to children about how they are feeling.
"It's been a lonely time for children," she said.
"Even though there have been opportunities to interact with their classmates on screen... they have still been on their own, in their homes, they've missed their friends, and we've seen quite high anxiety.
"They've come back really well, but it is quite clear that some of them have struggled during that time and there has been a lot of loneliness and self-doubt."
Mrs Hodder said the school was keen to seek support quickly.
"Self-esteem and self-worth is really important within the children. We know anxiety has been a bit of an issue, and self-esteem has been an issue, and unless we address that early on it affects everything they do," she said.
"Projects like Revealed Projects, an opportunity for somebody to come in from outside the school, can be really powerful.
"It opens up the dialogue with their peers, on what is really a sensitive subject, and actually the most valuable thing is that you're not alone in feeling like this and often those conversations don't happen without mediation."
Ms Sutton said the project needed extra funds to keep their services going, and with the hope of extending them further.
"We want to make sure that our services remain as accessible as possible," she said.