This channel is BEST place on YouTube for non-adult blindfold videos: https://www.youtube.com/channel/UClC1dfFWk3m_dw_eyilxm_g/playlists
There are tons of ideas for blindfold games with children. Here is one example of a Russian girl exploring playground equipment blindfolded. So Aleksandr Avramenko, great work, keep it up! And if you see this please drop me a line.
Please note almost all his content is clean but still check before showing your children