I started off with a pile of pompoms, an empty egg carton, colored pencils, scissors, glue, and construction paper. I had 8 colors of pompoms, so I cut off two rows of the egg carton.
To close up the egg carton, I cut off the top with an approximate extra inch and a half.
Cut two slits into the top, folded them in and taped it.
Cut the center out of each of the bottom sections next. This egg carton was set up perfectly to accommodate this.
Each section was then covered with a color of construction paper that coordinated with the pom poms. I glued the papers on, then reopened the holes. Doing it this way ensured that I wouldn't make the holes too big.
To make boxes I cut rectangles from the construction paper, slit the corners about 1 inch in,
glued each corner,
and patiently held them until they were dry.
On more construction paper I wrote the color in English cursive, romaji which is the romanized version of the Japanese language, and then in katakana at the bottom. I glued each of these sheets onto the bottom of my boxes and filled them with their coordinating pom poms.
I managed to get it set up just before he woke up.
Here he is after he matched all the colors, sorting them back into their boxes to start over.