h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

France is divided into 95 'departements', rather like British counties or U.S. States. All car registrations have the departmental code on the number plate.

List the numbers 1 to 95 on a sheet of paper and cross through them when you spot a car from that department. If you want to teach the kids a little geography, list the names next to the numbers and they'll soon tell their Ariege (09) from their Tarn-et-Garonne (82).

One further hint - as this can be played over several days, attach the paper to a clipboard so it doesn't get trashed in the car. Clipboards are really useful for any writing/drawing game, and can be borrowed from work!

This also works well in the Irish Republic. The middle section of letters on the Irish registration plates refers to the county of registration (e.g. MO = Mayo). Have them make a note of all the counties, and tick off when they see one from a particular county. Counties such as Dublin (D) and Cork (C), having large cities in them, will be the first to be ticked off. But it can be fun waiting for ages for a car from Laoise to pass. You'll also find that the kids learn the Irish form of all the county names, which is obviously a very seful skill.