A star is born/Build a better Mousetrap/Why I love my nieces

I have twin nieces, eight years old, who are inveterate entomologists, intrepid explorers, inventors and all around amazing people. A few weeks ago they found 56 grubs of unusual size, as big as my thumb, actually, living in a hole in a tree near their house. They took them home and have been cultivating them ever since, carefully feeding them the decayed leaves they love, and taking out of the box the incredible dirt the grubs produce after they've consumed the leaves. Now, apparently, one of them is packaging up the grub's "product" to sell as "Grubby Girl Organic Fertilizer."