The National Union of Students Wales held a training session for college representatives to teach them how to lobby politicians, chair meetings and run campaigns.
Some 26 Welsh FE colleges are affiliated to the NUS, but until recently only Pembrokeshire college showed any discernible union activity.
James Knight, deputy president of NUS Wales, said: "The level of union development in FE is, frankly, atrocious. But it is not a question of student apathy.
"FE unions have no money and traditionally FE culture has been different from HE. But that is changing as the distinctions between the two become blurred.
"We are campaigning to raise awareness of the benefits of having a strong student union in FE colleges."
Those benefits extend to the college, with many students swayed when deciding where to study by the support, facilities and social activity which unions provide, said Mr Knight.
Unlike HE institutions, which are legally bound to give financial support to student unions, with the largest universities paying out more than pound;1 million a year, FE colleges have no such obligation.
Mr Knight said: "Only four Welsh FE colleges give financial support to unions. NUS Wales is now trying to include FE much more by waiving registration fees to make our events more open. We have put money aside to help FE unions to get involved."
About a dozen college unions have become more active in the past year, and about 20 representatives were expected at the training session in Swansea.
Scott Westron, NUS president at Swansea college, said: "We are working with senior managers to ensure that the student voice is communicated effectively."
College principal Maxine Room said: "The newly formed student union shows our commitment to place learners at the centre of the business."