The Squirrels Who Squabbled, by Rachel Bright

Greedy squirrels Cyril and Bruce both have their sights on a very special prize: THE VERY LAST NUT OF THE SEASON! As the nut bounces crazily though the forest, the squirrels race after it, between the trees, over boulders, down the river and - ARGH! - right to the edge of a waterfall! Working together might be the only way to save themselves now ...