Vertical abacus

Vertical abacus for children and ederly with montessori colors to learn the numbers easy and fun.
- Touch to put or remove balls in the abacus
- When you reach 10 balls you have to remove all of the column and add one to the next to the left. The balls move to warn you that you have 10.
- Touch sign to change add and subtract
- Touch box for random number or reset
- Touch right or left arrow to add or remove a unit
- Press and hold the right or left arrow to fast forward or rewind
- Learn the concepts of:
---- Units
---- Tens
---- Hundreds
---- Thousand units
---- Tens of thousands
- Learn to add and subtract
- Button to check the result