Math is one of my strengths. I really enjoy it. Unfortunately not all of our children follow in my footsteps. Whether or not it is something they enjoy as I do isn't important. It is important that they be able to figure basic problems applicable to real life. One of the best ways for them to learn is in daily practice and practical use. Shopping and farming are two perfect ways for them to learn. In addition I like to play games with them to encourage use of basic math facts while we are having fun. Sunya Publishing has created a fun card game with multiple ways to play for a large age range to enjoy. Sunya - The Magic and Wonder of Math and Science Multiplying & Dividing has been a nice addition to our collection.
The book has a feel of India too it. It is very wordy in over explaining. The examples are helpful. The word "Sunya" is from ancient Indian Sanskrit meaning "empty or void of any quantity." Instead of 'Uno', you say "Sunya" when you are out of cards. The book also includes a history of the modern numerical system from Hindu Arabic Numeral System and Brahmi Numerals.
I'd do more research before introducing these systems to your children. As a Bible believer, I know that Noah and his family brought God's original language and accounting of the sciences with them on the ark. I also know the ark landed in Turkey and the languages and people were dispersed from the Tower of Babel most likely in Iraq. That knowledge was then spread throughout the world. There are lots of archaeological discoveries constantly being found all over the world that prove all the ancient people had very advanced knowledge. All advanced civilizations should be considered and studied through a Biblical worldview.
All in all, Sunya Publishing has created a fun game with lots of possibilities. Sunya - The Magic and Wonder of Math and Science Multiplying & Dividing can help help enforce basic math concept.