If you want a school trip to go with a bang, take a day trip to the Royal Gunpowder Mills in Waltham Abbey, Essex. Dotted with 19th-century buildings, the place is something of a hidden treasure and is not without its quirky side.

The mills are where gunpowder and other explosives were made for the British military. When it ceased to be an explosives factory after the First World War, the site became a top-secret research establishment. It was here that Sir Barnes Wallis carried out many of his experiments to invent the bouncing bomb for the Dam Busters in the Second World War.

The site is now open for schools and other day trippers. It offers a range of educational activities, the most popular of which is the annual “Gunpowder, Treason and Plot” event. Though Guy Fawkes didn’t visit the mills, he was a customer of its main product.

The day involves learning about the plot, meeting the characters (in appropriate costume) and getting a taste of Stuart food. This event takes place around Bonfire Night and is usually heavily booked (especially for this year’s 400th anniversary). Other programmes on offer to schools include “Victorian Life”, “Home Front” and “Victorian Christmas”.

Each provides a full day of fun and activities and lots of opportunities to meet folk in costumes, learn about food, dances, customs and culture of the period.

“Victorian Life” is the latest addition to the education programme that offers to help youngsters learn about everyday 19th-century life through a school lesson (with appropriate school ma’am, chalk boards and ink wells).

They also learn about how children kept themselves amused in holiday time (and no, this does not involve gunpowder).

The “Home Front” programme allows children to experience life in a small wartime “village” and meet people at work during the war. They will be introduced to Miss Thomas, grocer and school mistress, Mrs Smythe, the evacuation officer, Mrs Elkin, pilot and adventurer, and Miss Hinton, an air raid warden.

“Victorian Christmas” is another innovation. Classes can travel back in time and meet Colonel Brakenbury, his family, friends and mill workers as they celebrate their Christmas. They learn about Christmas traditions - the tree, holly, food and carols. They make decorations and cards using screen printing. They also play traditional parlour games and find out what it was like to amuse yourself without computers or television.

The main exhibition building traces the history of explosives through the ages and a really first-class short film is played throughout the day - it follows the invention of gunpowder by the Chinese and takes the story up to the present day. The exhibition is very well done: lots of hands-on displays including a “design a bouncing bomb” simulation. It has to be said that, with the exception of the main exhibition, there is a “work in progress” feel to the place.

Many of the other exhibitions lack the style and sophistication you might expect from other museums. It’s clear that lack of funds have prevented this museum from being in the top league of attractions but, in some ways, it is all the more charming for that. “The Blitz Experience”, for instance, is a small scale affair in a large hut which houses a reconstructed 1940s shop and an air raid shelter complete with sound effects. It is simple, but the children who visit get a thrill from the atmosphere created by the willing band of enthusiastic volunteers who run the place with verve and devotion.

There are many derelict buildings awaiting funds so that the entire place can be opened up.

Some children may love the exhibition of historic firearms (others, including some teachers, may be uneasy). This is a private collection of small arms and militaria displaying more than 200 working guns from the English Civil War to present day conflicts - matchlock to Kalashnikov.

Visitors are encouraged to learn how to load, cock, aim and fire a variety of machine-guns and rifles, and there are certificates for those who qualify.

There is a huge amount to do at Royal Gunpowder Mills. There is also an extensive nature trail and many outdoor activities on offer so you don’t have to love big guns or loud bangs to have a great day out.

Royal Gunpowder Mills, tel: 01992 707370; www.royalgunpowdermills.comschools_education_progs.htm