In Trafalgar Square the vibration of earthmovers and drills announces that something new is being created behind the hoardings around this landmark site. Pedestrianisation of the north side of the square will open up a piazza stretching from the National Gallery to a new roundabout circling the statue of Charles I on the south side.

While the capital’s motorists and pedestrians curse the disruption, we National Gallery staff look forward to a moment early next year when we’ll be able to hear the fountains for the first time.

Meanwhile, inside the National Gallery, the idea of urban spaces under construction is beautifully mirrored in a work by the 18th-century painter Canaletto.

“The Stonemason’s Yard” is the nickname for the more prosaically labelled “Venice: Campo S Vidal and Santa Maria della Carit... (The Stonemason’s Yard)”. Unlike Trafalgar Square, this is not a picture-postcard view of the kind Canaletto was later to paint of his native Venice, but a view most likely well known only to the Venetian who probably commissioned the work.

We are looking across the Campo San Vidal over the Grand Canal to the church of Santa Maria della Carit... and the facade of the Scuola della Carit.... The square has been transformed into a temporary workshop, most likely for the repairing of the nearby church of San Vidal (not seen in the picture), with scattered blocks of white stone brought across the Adriatic from Istria (today part of Croatia and Slovenia).

The view remains recognisable today, although there have also been some dramatic changes: the campanile of the church of S Maria della Carit... fell down in 1744 taking with it the two white houses in front. The Scuola della Carit... now houses the Accademia Gallery, and today the view is dominated by the wooden Accademia bridge which touches down where the two white houses are shown in the painting. The Campo is now paved over, but the house on the right is still there today, and even the well head from which the woman on the right is drawing water still stands firmly at the centre of the Campo.

Painting people

As Trafalgar Square will be in the future, so this view is also brought to life by the people in it. Masons shape stone in the yard and another can be seen working inside the workmen’s hut on the right. On the left a mother leaves her sweeping to rush to her crying (and peeing!) child who has fallen backwards; an elder girl looks on smugly (“nothing to do with me”), while a woman peers down from the balcony above her to see what the commotion is about.

On the balcony of the house on the right a woman spins yarn in the early morning sun shining from the east. A cockerel crows from the window in the left foreground. In the middle and background, gondoliers work on the canal, women hang out washing, and others sit watching and chatting.

Details in space

As in all his work, Canaletto gives great attention to details: a pot of herbs on a window ledge, the masons’ tools or a patch of shabby plasterwork.

When you start to explore the spaces, you gradually become aware that Canaletto is leading you in an almost physical way from one spot to another through his extraordinary ability to paint light and shade: you pause on the bright hot dusty ground to watch the family drama, then sense the cool shadow of the building next to it.

Sharp contours of a gondola catch your eye - you cross the green canal and see the sunlit houses, contrasting with the crazy abstract shadow of the campanile on the wall next to them, and so on throughout the image.

People often think of Canaletto’s paintings as topographical views but he constructed them with artifice. He often used more than one viewpoint, altered the shape of buildings and sometimes even included buildings that were not there. But the pictures are all based on a knowledge of the city’s appearance and this largely accounts for how Canaletto has shaped people’s image of Venice.

Classroom tips

* Oral work

An image such as this is so rich in detail that there are many ways you might use it in different subjects. A perfect introduction to key stage 12 children to keep them guessing might be to cover the image with a piece of dark card into which you’ve cut advent calendar-style windows. Have them open one a day, and build in their minds an anticipation of the whole. Such an activity will naturally lead to the “good quality oral work” which the National Literacy Strategy stresses.

* Written work

Many primary schools now use pictures to stimulate writing in different styles and as a source for word-level work particularly at Foundation level and KS1. For “The Stonemason’s Yard” writing might include at KS1 simple “What can you see?” books with a different detail from the picture on each page. Older children could write descriptions of the view, or speech bubble conversations between the figures, then simple playscripts.

* Maths

The picture also lends itself to maths activity: 2D and 3D shapes abound and if you were working on triangles, getting children to find and name the types of triangle would be an engaging activity. If co-ordinates were your topic, you could place a transparent grid over the picture and ask children to locate objects.

* Humanities

In the humanities this image fits into history and geography as a record of a specific place at a particular time. Complement these contexts by playing Venetian music of Canaletto’s day.

* Secondary

Secondary art teachers might use the picture as a reference when working on light and shade; students could then make drawingspaintingsphotographs of their own urban environments on a sunny day.

Ghislaine Kenyon is deputy head of education at the National Gallery

‘The Stonemason’s Yard’ is in the National Gallery’s permanent collection and free gallery talks on any theme which could include it can be booked by contacting the Education Department Tel: 020 7747 2424.

It is available as a postcard or slide from the National Gallery shops or by mail order Tel: 020 7747 2870 www.nationalgallery.org.uk National Gallery Education is also running primary teachers’ courses featuring a session on The Stonemason’s Yard Tel: 020 7747 2424 The National Gallery is in Trafalgar Square, London WC2N 5DN