Investigating the relevant collections at the Museum of Oxford in anticipation of its Medieval Day for families on April 17, and wondering what had been on this site (at the junction of St Aldate's and Blue Boar Street) in the Middle Ages, I stumbled across an interesting part of the city's history: the contribution made to its business and academic communities by the first Jewish immigrants.

The other flourishing business in Oxford during the early Middle Ages, leatherworking, is represented by, amongst other things, a buckled shoe from the 13th or 14th century which has been strangely slashed - possibly, the curator suggests, as a rather drastic means of relieving pressure on a painful bunion (or perhaps one of the nasty swellings symptomatic of the Black Death?) Interesting reminders of other medieval city crafts include several tiny metalworking crucibles found on the site of the Examination Schools, and many examples of jewellery - the copper hat ornament in the form of a cockerel is particularly nice.

A strainer made from animal bone, and some jugs and cooking vessels - specimens of the Brill/Boarstall area pottery whose workshops were the source of much local everyday tableware of the time - introduce a section on the domestic arrangements of Oxfordians in the Middle Ages.

Though there is nothing left of the city's smaller houses, a few fragments of larger ones survive, and some pieces from these, which today's woodworkers will appreciate for the quality of the joints, can be seen in the museum.

The mint in medieval Oxford is examined through a series of silver pennies from different reigns, bearing a variety of spellings of the city's name: OXNA, OXNAFORD, OXSEN and OXENEFOR were all used at one time or another. Beside them is a set of folding balance scales, no more than three inches high, made for testing the weight of the coins.

The establishment in the Middle Ages of the first Oxford colleges - Balliol, University, Merton and Exeter - and the monasteries of the Dominicans (Blackfriars) and Franciscans (Greyfriars) - was associated with a thriving book production industry. Visitors can see lead styli, excavated in St Aldate's and on the site of Blackfriars, which were used to inscribe wax-covered tablets - the equivalent of our Post-it' notes.

There is also a collection of parchment prickers - small pieces of bone with metal points, which were used in pairs to mark out the lines on parchment before writing.

Families coming to the Medieval Day activities will meet a fully-equipped knight from the late Middle Ages (recreation specialist Ian Poyle, pictured) who will deliver some stirring speeches from Henry V and Richard III, and talk about most aspects of domestic life and warfare, including the political circumstances leading to the Wars of the Roses - note that he is a Yorkist, so maybe Lancastrians would do well to stay away.

He will bring along a selection of gruesome weapons, and individual pieces of armour, which demonstrate its evolution during the medieval period. Children will be able to handle these and get some idea of the discomfort and inconvenience involved in wearing them.

There will be craft workshops for five to 12 year olds, based on the connection between medieval knights and the legend of St George - participants can make their own shields, and model dragons.

There is also a permanent replica brass rubbing trail, which includes a scaled-down local worthy, John Poyle of Hampton Poyle, from the 1400s, wearing a complete suit of plate armour. His wife, Elizabeth is shown in the fashionable Crespine headdress, with her hair gathered back on each side of her face.

Museum of Oxford, Town Hall, St Aldate's, Oxford OX1 1DZ. Open Tuesday-Friday 10am-5pm, Saturday and Sunday noon-5pm. Entry to galleries free Workshops on April 17 (booking advised), £2.50 each - Medieval Monsters 10am-11am and 2pm-3pm; Heraldic Shields 11.30am-12.30pm and 3.30pm-4.30pm. Brass rubbing pack £1.

A new panel is currently being put together which gives museum visitors an insight into life in the medieval Jewish quarter. Jews settled in the commercial centre of Oxford - what we know as St Aldate's, which came to be called Great Jewry Street - from 1080 onwards, making a living in the traditional way from trading, medicine, or money-lending.

Near the corner of Blue Boar Street a number of triangular pigeonholes were found in a cellar wall - it has been suggested that these were used by Jewish merchants for the storage of contracts, along the lines of the wall recesses in which Christian monks kept their manuscripts.

Jewish residents also let housing to students, and, although barred from the University unless they converted to Christianity, were often consulted by clerics on matters of Hebrew scholarship.

Their synagogue, founded in 1228, was situated where Christ Church's Tom Quad now stands, and their cemetery was beside the Cherwell, on the site of today's Botanic Gardens.

The present 1897 Town Hall, which incorporates the museum building - until the 1970s the city's public library - is built on land once owned by two prominent Jewish residents, Moses ben Isaac and David of Oxford. It passed into other hands after Edward 1's expulsion of the Jews from England in 1290. An excavation of the area uncovered many pegs of the sort used for tuning stringed instruments, and the records of Oseney Abbey at the time reveal that a harpemaker', one Thomas Brickar, occupied three tenements on this site.

Some of his harp pegs are displayed, in a sequence which demonstrates their manufacture, beginning with the raw material in the form of an ox or horse leg bone.

Instrument-making is just one of many medieval crafts and trades featured, the physical evidence for which has been gradually unearthed on digs throughout the city and which is presented selectively here in a way that children will find approachable.

Much of Oxford's increasing prosperity in medieval times - which the museum defines as 1154-1485 - came, of course, from its trade in wool and cloth.

Visitors can see a 14th century seal of the Oxford Weaver's Guild, which found its way to Cavendish in Suffolk, another wool trading area. Also on show is part of a woolly garment, disinterred from a coffin on the site of the medieval St Budoc's church in Paradise Street.