Fasciné par la magie, Caillou veut reproduire le tour que lui a montré mamie. Avec un peu d’efforts, beaucoup de patience et un accessoire magique – un composteur –, il transforme des déchets de table et des résidus verts en nourriture pour les plantes!

Caillou loves magic. Grandma impresses Caillou so much with her “composter” magic trick that Caillou has to try it too. He goes home and turns scraps of leftovers, grass clippings, and apple cores into plant food!

When Caillou helps Grandma in the garden, she shows him how scraps of leftovers, grass clippings, and apple cores can be turned into compost, that can then be used to nourish the plants in the garden.

"Grandma shows Caillou a great magic trick: turning scraps of leftovers, grass clippings, and apple cores into plant food"--P. [4] of cover.

At day care Caillou learns about water conservation. Once at home, he looks for ways that he can save water. Because his suggestion of not taking any more baths is vetoed by Mommy, Caillou has to find other ways to conserve—every little drop adds up!

Caillou learns how to make his bike look new again by using things he already has.

"Caillou helps Daddy choose a new tree. He learns that trees are very important for the Earth and for the birds"--Page 4 of cover.