The atmosphere, mid-May, in the Edinburgh College of Art, is eerily calm.

Corridors which until recently sounded with the clatter of final-year students working frantically to set up their degree shows now sound only to the footsteps of the assessors. All that remains is the work. In a few days, the students will know the results of four years hard - or hard-ish - graft. And in a few days, too, the public will be allowed into this labyrinthine building, with its wooden floors and vast windows looking on to Edinburgh Castle, to view the work of the latest generation to emerge from the capital's respected art college.

Stuart Bennett, Head of the School of Art, is sanguine in the face of all this freshly packaged, hopeful creativity. The products of his demesne, comprising Painting, Photography, Sculpture and Intermedia (BAs) alongside a variety of postgraduate disciplines, are shown in tandem with work from the School of Design (Jewellery, Product Design, Illustration, Animation) and the School of Architecture and Landscape Architecture.

In the main building, it is the painters who occupy the north-facing rooms, the tall windows making the most of the flat northerly light and providing an inspirational view of the castle - although one imagines that castle has, for the artistically-blocked, been the stuff of nightmares too. The brighter south-facing rooms are the preserve of the rest, from the photographers on the ground floor to the sculptors in the basement.

A short walk down the road, the Designers, Jewellers and Illustrators are racked up in the high-rise Evolution House.

If the disciplines are strictly delineated, Bennett points out that the boundaries of practice, in recent years, have become more blurred. "Our practice is post-media. I think that the interesting thing when you do have these material distinctions, is that it is where the edges meet that's really interesting.

''You learn nothing, if you're a painter, by only talking to other painters. As long as you've got a lateral crossover between disciplines, you can get really interesting discussions. I'd one sculpture student who was brilliant, but she was making photographs. And she'd never have been making photographs like that if she'd studied photography."

The lateral crossover extends, too, outside the College campus. Bennett notes that now that ECA is part of Edinburgh University (the official merger occurred in 2011), students can take electives across the University in the first year. "We've got students taking anthropology, say, and using ethnographic methodologies in the studio." It is all part, now, of the rich tapestry.

The degree work itself is as diverse as one might expect. There are sober thinkers, humourists, obsessives and navel-gazers. Work is gaudily splashed, or intricately gauged. There are ideas here that feel substantial and inspired and others that are a little wispish or inconsequential. From a room of naïve overblown posters, a sudden reduction in scale to a tiny startled pig perched on the firing arm of a miniature wooden trebuchet.

A student, who apparently prefers to live in the virtual world, projects a live feed of himself on to an insufficient plaster model. And, billboard-size, a photograph of a man standing on a concrete block, a classical orator, a salesman, in front of an encroaching sea, is both dramatic and arresting. Downstairs in a corridor giving off to the sculpture rooms, a voice booms "Scotland, England, Scotland, England…" over two film panels of Hadrian's Wall and a black Labrador on opposite walls - both exactly the same, yet reversed - a lone step into current political debate.

For the first time, this year the architecture students are showing in the main sculpture court under the blank eyes of the classical plaster casts lining the upper balcony. And yet there is something very pleasing in the contrast of scale between the massiveness of the building itself and the diminutive architectural models below, some teetering on the edge of their plinths with miniature grandeur, others sprawled out, complete with millimetres-high occupants, scurrying between these intricate constructions of the mind.

The key to marking these works, Bennett tells me, lies in the neat folders of written material that lie alongside every degree show. Inside are critical essays by each student, research reports on where the work comes from. "Not what it's about," stresses Bennett, "but why they do it and how it relates to current practice. Documents like this are very helpful for us, because what we're assessing is not how good we think the paintings are, but what the students have learnt as evidenced through the work that they've made. That way, we're not critical of the work, but critical of the way the work is articulated. It's an important way to divorce the subjective from the objective."

It has not always been done this way, Bennett tells me. The traditional view, after all, of the art college is of students brought under the wing, offered space and time, as grandee tutors "descend and bestow their wisdom". The subjective conclusion, now, is left to the viewer who enters the building through a phalanx of life-size puppets in the foyer, a ready-made celebration party toasting the visitor - and the graduating students -- with plastic champagne glasses and fixed gazes.

Edinburgh College of Art Degree Show 2014, 74 Lauriston Place, Edinburgh (0131 651 5800, www.eca.ac.uk) until June 1