No, this is NOT an insect. It's the "skin" of an insect ! This thing was brought to me by my ten year old son who found it in the garden.
The Cicada is an insect well known for its song which can be heard during summer in warm countries.
Its life cycle lasts several years depending on species. At the final stage, the nymph clings to the bark of a tree, and moults, meaning that the insects sheds its skin and emerges as an adult. This skin or exoskeleton, or exuvia is left behind, still clinging to the bark of the tree.
This fascinating exuvia is hollow, and has an opening on the back, through which the adult insect has emerged.
It measures 2 to 3 cm in length.
The picture below shows how the (green) insect emerges from the exuvia. Photo by Jerôme Salort (http://www.jeromesalort.com/album-1930610.html)
Also check this site to witness the complete sequence :