The nationwide helpline "meic", launched in May with more than pound;450,000 of funding from the Assembly government, gives children the opportunity to find help on issues important to them, including concerns around education.
In the first few weeks, exam stress was among the main concerns of callers, and recently advisers have received many calls about bullying, among other issues.
Deputy minister for children Huw Lewis said: "The number and nature of calls received so far underlines the need for this service.
"Children and young people have a right to be heard and have their concerns listened to, no matter what the issue. This service provides a valuable channel of communication while complementing other important services for children and young people".
Trained advisers provide information, let them know where they can get further help, or transfer them to an independent professional advocate. The service runs seven days a week from midday to 8pm but will become a 24-hour operation later this year.
There were many calls in the half-term break; a similar rise is expected during the summer holidays.
Children and young people under 25 in Wales can contact meic by: freephone 080 8802 3456; free text to 84001; instant message via www.meiccymru.org.