From pi and Pythagoras to presidents and popes, prime ministers to prime numbers, literature to litmus tests, there is so much information from our school days that we have forgotten, or only half-remember. Designed to dust off those cerebral filing cabinets, The I Used to Know That Activity Book is an enjoyable and interactive way of reminding ourselves of all those facts that we'd like to remember and re-learn, or those we missed the first time round! The book contains questions across all subjects, perfect to dip into and try your hand at whenever the mood takes you. There is space to fill in the answers and, if you are a bit rusty, all solutions can be found at the back of the book. This is an enjoyable and lighthearted activity book for any adult, or fan of the original book.