It looks like about an hour a day for a year or two for the first certification. The to-do list follows.
1.1 Read Soroban handbook
1.2 Watch videos on youtube
1.4.1 The Abacus: The World’s First Computing System: Where it Comes From, How it Works, and How to Use it to Perform Mathermatical Feats Great and Small The Abacus: The World’s First Computing System: Where it Comes From, How it Works, and How to Use it to Perform Mathermatical Feats Great and Small
1.4.2 Advanced Abacus: Theory and Practice Takashi Kojima
1.4.3 The Fundamental Operations in Bead Arithmetic – How to Use the Chinese Abacus Kwa Tak Ming
1.4.4 Japanese Abacus Use & Theory Takashi Kojima
1.4.5 Speed Mathematics Simplified Speed Mathematics Simplified Edward Stoddard
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4 thoughts on “Practicing the soroban”
I shall bow to you… Soroban master.
Vicky Rettke liked this on Facebook.
I liked your focus on the soroban. I made a short tutorial on how to make your own soroban http://japanmath.com/how-to-make-a-soroban-japanese-abacus.html that will be of interest with your more frugal readers 🙂
Delightful! Thanks so much for sharing that.