It can be used by low-ability pupils to produce their own language - eg, by changing "Der Hund ist klein" to "Die Katze ist klein". They can then be encouraged to change the adjective, "Die Katze ist alt", then add an adverb, "Die Katze ist sehr alt", then maybe change the article, "Meine Katze ist sehr alt", and so on. This puzzle-like approach stops them trying to translate literally from English - always a disaster.
Higher-ability pupils like the challenge of seeing how much they can change a sentence. It encourages them to observe the structure, keeping the grammar accurate. When pupils come to write a piece of coursework, they find they can use source material properly, not plagiarising but manipulating the language to create their own original sentences. The concept is very helpful in getting them to see how the grammar works and the more able pupils take greater risks with the language.
Elaine Pratt, head of languages, Keswick School, Cumbria