This activity book has a section where you decode ancient symbols.
GTO: 14 Days in Shonan, Volume 7 (Great Teacher Onizuka)
You will find that the illustrated diagrams explain things clearly.
GTO: 14 Days in Shonan, Volume 7 (Great Teacher Onizuka), Fujisawa, Toru, Excell
A nice touch in this activity book is the peel-and-stick reward badges.