Sinclair, Wonder Bear — Malorie Blackman

Sinclair is no ordinary teddy bear. At night, when his owner Emily is fast asleep, he becomes a Wonder Bear, flying all over the world, and magically changing himself into new materials to save people in danger. One night he's a very busy bear indeed. First in India, he changes into steel to mend a broken track before a train full of people arrives. Then in France, he transforms himself into a powerful magnet to help the Madame free her pet dog Lucile. In Australia, Sinclair turns into a window in a glass-bottomed boat to help his friend Captain Baz. Then he becomes stretchy rubber to save a little boy from the water. But after all that hard work even Wonder Bears get sleepy, and as the sun rises, he flies home to Emily before she wakes up.