This was turning out to be an unusual visit to the beach for five-year-old Rosa: no pleading for ice-cream, no ritual burial of her father in the sand, and no attempt at a coastal voyage on a Barbie inflatable.

Instead, the afternoon found her hunched over a wooden box full of sand, on the shore at Lyme Regis, Dorset, with a gaggle of other children. After five minutes of handiwork with what looked like a large blusher brush, Rosa had uncovered the skeleton of an ichthyosaurus, a marine reptile that lived at the same time as the dinosaurs. It was a fake, of course, planted by organisers of the Lyme Regis Fossil Festival. Not that any of the children minded, so excited were they at the idea of being a fossil hunter.

This annual event, which has been held for the past three years in late spring, is just one in an increasingly crowded schedule of family-friendly science-themed festivals around Britain. The best known are the Cheltenham Science Festival, started in 2002, and the Edinburgh International Science Festival, a hardy annual since 1989.

The Government’s Office for Science and Technology estimates that there are 15 annual science festivals held around the country. Oxford, Cambridge, York and Newcastle have yearly events; so do Brighton, Shetland and Moray. Their popularity is growing: Milton Keynes kicked off its first science festival yesterday (until July 15) and Manchester’s week-long debut is in October.

Their purpose goes beyond enlightening the masses about whether we originated in a Big Bang. They also attract a stream of tourists, as we discovered when we tried, unsuccessfully, to book hotels near Lyme Regis (we ended up at my inlaws in Somerset).

Grant Seeley, one of the organisers of the Milton Keynes Festival, hopes that the town can enjoy similar success. The festival, whose inauguration forms part of the new town’s 40th birthday celebrations, will feature events at Bletchley Park, the war-time nerve centre that cracked enemy codes, and at the Open University, home to Professor Colin Pillinger’s well-publicised Mars exploration project.

Seeley bristles at the idea that the new town, famed for its concrete cows and proximity to Birmingham, is not an obvious scientific tourist destination. “The Open University has some of the world’s leading scientists in space exploration, and they have a Mars landing vehicle sitting in the corridor,” he says. “People go to the States to see that.

The idea is that kids and their parents can come and listen to these scientists and talk to them, and then visit the observatory. We want to develop the festival year on year, so that we will also get national and international visitors.” The festival also hopes to turn children on to the idea of a science career, with the town’s high number of research and software companies eventually benefiting.

With such a crowded festival calendar the key to a successful sciencefest is quality. Standards have soared considerably, and a handwritten banner above a few rickety tables no longer cuts it. Some now boast star names such as Professor Richard Dawkins and Baroness Susan Greenfield (they appear regularly at book festivals too, highlighting how science has gradually wormed its way into high culture), and full-on theatrical productions. These often cost the same as a cinema ticket, although an evening with Bill Bryson, whose engaging science opus A Short History of Nearly Everything won the genre’s top prize, beats two hours with Bruce Willis any day.

One big factor in attracting me to the Lyme Regis Fossil Festival was the involvement of scientists from London’s Natural History Museum (NHM), to which Rosa drags me at least once a month. The idea that she could have a hands-on fossil experience with experts appealed greatly.

The museum housed its activities – ranging from panning for fossils to making a Jurassic storybook – in a giant marquee. Elsewhere, children could make and paint small plaster casts of ammonites, the snail-like sea creatures that danced in Jurassic seas.

There was also an appearance on the beach by Mary Anning, the Victorian fossilist who scoured the Dorset coastline in long skirts and bonnet and sold her specimens to admiring London gentlemen (she is rumoured to have inspired the tongue-twister “She sells sea shells by the seashore”).

Anning was a pioneer of her time; she was motivated as much by science as by money, and, despite her sex, she was much fêted by the learned societies of London. Her finds still take pride of place in the NHM today. Anning was played charmingly by the costumed actor Miriam Cooper, who Rosa had once stalked for two hours around the NHM.

Even without a festival, a visit to Lyme Regis and nearby Charmouth, which form part of the 95-mile Jurassic Coast, a World Heritage Site, is never a bore. Charmouth is home to the Charmouth Heritage Coast Centre, a mini museum with fossil finds, interactive exhibits and a theatre. It can book fossil walks, where, with the help of a guide, you can uncover your own specimens.

Or, as we do several times a year, you can traipse unaccompanied over what would have been the sea bed 200 million years ago, carefully scrutinising the freshly fallen rocks for geological treasure, visiting the fossil shops to gaze covetously at their beautiful, expensive ammonites, eating crab sandwiches on the pebble beach – and finally succumbing to the plea for ice-cream.

Anjana Ahuja writes the Science Notebook column for The Times.

Budding boffins

This summer’s science festivals: Milton Keynes Science Festival, on until July 15 (www.mksciencefestival.org.uk). Orkney Science Festival, Aug 30-Sept 5 (www.oisf.org). The BA Festival of Science, one of the biggest annual science events of its kind, attracting international names to a different location each year. This year it is in York from Sept 9-15 (www.the-ba.net/the-ba/events/festivalofscience).

Other science festivals: Oxford Science Festival, January; Brighton Science Festival, February (www.brightonscience.com); Edinburgh International Science Festival, April, (www.sciencefestival.co.uk); Cheltenham Science Festival, June (www.cheltenhamfestivals.com).

Science attractions:

Science Museum, London (www.science museum.org.uk, free admission). Perfect day out for all budding boffins.

Natural History Museum, London (www.nhm.ac.uk, free admission). Prime destination for fossil enthusiasts.

Natural History Museum at Tring, Hertfordshire (www.nhm.ac.uk/tring, free admission). Birds and other animals.

Eden Project, Cornwall (www.edenproject.com, family ticket is £35). Explore the famous glass biomes.

Explore@Bristol (www.at-bristol.org.uk, family ticket £26.). Hands-on science centre.

Thinktank, Birmingham (www.thinktank.ac, family ticket is £49.50). Interactive galleries with planetarium.

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