Peter Lea Primary in Cardiff is believed to be the first school in the province to introduce antiseptic hand-wash dispensers in its corridors and canteen. The dispensers give out a hand gel that could kill germs and that way cut sick days.
The initiative is being led by pupils through the School Council and supported by staff as part of its Healthy Schools campaign.
And after just a few weeks of use, early indications show pupil sickness is down.
The hand gel works in the same way as that used in hospitals to reduce the spread of superbugs such as MRSA.
The School Council - which is made up of representatives from each class - is now hoping to prove the case for the introduction of the hand gel in all schools by monitoring the sickness absence this academic year and comparing it with last year.
School council member Bailey Vatsaloo, aged 10, said: "We introduced the hand sanitizers as part of our Healthy Schools campaign in which we learned about eating healthily and exercising.
"To stay healthy it is important to wash your hands and get rid of germs.
"We have 14 soap dispensers in the corridors and one in the canteen so that pupils can wash their hands when they come in from the playground and before they eat their lunch.
"It has already improved the level of sickness in the school and pupils are using the sanitizers responsibly - only when they need to."
The school council introduced the sanitizers a few weeks ago after consulting with pupils and parents.
Council member Sofia Heke, also 10, added: "I think the sanitizers are a very good idea as they get rid of germs and help stop us getting ill.
"You don't need water, just the soap so it is very quick and pupils have been learning about the importance of hand-washing and when they should use the sanitizers."
Head teacher Peter Hodgkins praised the maturity of pupils in their campaign to improve handwashing and added: "The sanitizers have been placed in key areas around the school as an extra precaution but not in the toilets as we encourage all pupils to continue to use soap and water.
"We will be monitoring closely to see what effect they have on sickness absences in school over the next academic year."
A spokeswoman for education inspectorate Estyn said inspectors were unaware of any other school in Wales with these hand-gel dispensers.
The action at the Fairwater school comes as Wales' chief medical officer Dr Tony Jewell launched a campaign to encourage adults and children to wash their hands to help beat the Norovirus, also known as the winter vomiting bug.