More than half of next year's Leaving Certificate students are feeling unprepared to complete the CAO application form for college entry.
One in four current sixth-year students reported never having had one-to-one consultation with a career guidance teacher, according to a recent survey.
And a little more than half of the students said they had had less than an hour one-to-one consultation with a guidance counsellor.
The findings emerged in a survey of about 6,000 students - about one in 10 of the Leaving Cert class of 2015 - conducted by Studyclix.ie, an online forum for teachers and second-level students.
The survey found 56pc felt inadequately prepared to complete the form, 24pc never having had one-to-one guidance and 54pc having less than an hour's one-to-one guidance.
While not a scientific study, the findings will raise concerns as Leaving Certificate candidates prepare to fill in CAO forms ahead of the end of January deadline.
About two in three 18- and 19-year-olds apply for college, but there are concerted moves this year to encourage even more students to consider third-level.
Today sees the launch of the first ever College Awareness Week, aimed at increasing the numbers going to college from groups that are under-represented at third-level, such as those from lower socio-economic backgrounds.
Over 200 activities are planned in schools and communities around the country, highlighting the benefits of third-level education.
The Studyclix.ie findings echo a study by the Economic and Social Research Institute (ESRI), which tracked about 900 students through the second-level system and beyond, and found many ill-prepared for making decisions about college.
The ESRI found inadequate career guidance to help steer individual students towards the right path as a key problem.
On average, about one in six first year college students do not continue to second year of their course - they either drop out or switch courses - which is largely blamed on making the wrong choice.
The ESRI study pre-dated the cuts to school guidance services, introduced as a Government cost-cutting measure in September 2012. An audit by the Institute of Guidance Counsellors (IGC) last year found that there had been a 59pc reduction in time for one to-one-counselling since September 2012.
Around 200 schools were not offering any one-to-one service.
IGC president Betty McLaughlin said the greatest impact was on socially disadvantaged groups, which increased education inequality.
Children from lower socio-economic groups tend to be more reliant on a school guidance counsellor because their parents are less likely to have experienced third-level education or to have detailed knowledge about it.