Popular Keywords... Kodomo Challenge Character... Shimajiro This is a set of Kodomo Challenge educational materials. The batteries have been removed after confirming that the sounds work. These items have been used by a child, so there may be stains, scratches, and peeling stickers. The sound books show signs of use. Some materials are missing. All sound-producing materials have been tested and confirmed to work. Since this includes materials from Kodomo Challenge Petit, it can be enjoyed from 11 months old.