On a visit to their grandparents, Luke and Ruby come across an old notebook, which Nanny explains she and Grandad used for recording the experiments they conducted when they worked as scientists.

And so begins a series of domestic scientific adventures for the children. They learn how to identify and count the birds they can see in the garden and to note their appearance and behaviour; how to make simple musical instruments out of household objects; how to bake a cake following instructions; how to grow flowers from seed. And all the time they are learning essential scientific procedures such as note-taking; predicting and checking if their predictions are right and drawing sensible conclusions; doing experiments in a systematic way so that their findings are useful.