There were smiley faces all round at Ysgol Tregib, Llandeilo after its business team's highly innovative concept won the Year 9 award at the West Wales Celtic Enterprises competition, held at the Halfway Inn in Nantgaredig, Carmarthenshire.
"We do a lot of enterprise work here at Tregib and I always try to impress on our pupils the need to produce something different," said assistant head Tim Williams.
"We were looking for something topical which was not just about profit but a product that can also help people."
Mr Williams acknowledges that the vests, made out of reflective material, were "not very cool looking", so the pupils' response was to produce a series of smiley-face stickers, indicating the mood of the wearer.
"The stickers can be happy or miserable - if you fancy someone there's even one with a wink," he said. "I know it sounds crazy but it really works and has captured the imagination of our audience."
The smart-looking jackets, which cost pound;7, come in pink, orange, green and blue and have already caused quite a stir. "These jackets serve a useful purpose and people like the quirkiness of it," said Mr Williams, who feels the project has allowed pupils to gain an invaluable insight into the business world as well as developing vital communications skills.
"If we want to keep young people in rural areas such as Llandeilo, we have to offer them alternatives to working for large organisations," he said.
"Small businesses are the way forward."
A set of decorative rubbish bins proved an eye-catching winner for Llandysul's Ysgol Dyffryn Teifi, which won awards for the best display, and business plan along with the overall Year 10 title.
Calling themselves Trash, the girls sacrificed their dinner hours to turn discarded containers - including industrial-sized baked bean tins - into trendy bins.
They used material from a local upholstery company and personalised the bins with embroidered logos such as hearts, flowers or the name of a favourite football team.
"I think the secret of our success is that the idea is so original," said head of technology Anwen Williams, whose girls have been awarded an educational trip to Ireland where they will receive a Waterford crystal bowl.
"The girls all have different strengths. It also gives non-academic pupils a chance to progress and be successful. I look for pupils who have an interest and are willing to give up their own time."