21 Marbles

The Balconia Math series is designed by professional mathematicians to challenge and entertain children with attractive problems and games. If you want your child to develop clear logical thought, affinity for math, and perseverance, while playing games, this series is made for you.

21 Marbles was designed by Elitza Maneva (PhD, UC Berkeley) for her 7-year old son, with his continual help. He was having fun summing "very long" numbers, but kept getting slowed down because of forgetting whether it was 6+3 that was 10 or 7+4, or maybe 6+2... (Counting your fingers while holding a pen is just not very comfortable.) The memory problem was fully resolved by this game.

21 Marbles came out to be an elegant little logical puzzle enjoyed especially by children 6-11 years old. It helps the younger ones practice arithmetic, and it challenges the older children, adolescents and adults with what is essentially a quick and relaxing peg solitaire. The puzzles are different every time you play.

As often happens, a young reviewer put it better than we can: "This is a really nice educational game, with similar skill elements to sudoku: arithmetic on small numbers and "if this then that" type logic. It's more fun, has more action and colors than other such games and so it's especially appropriate for small children."

It's a magical peg solitaire. It's a brain trainer. It's an educational math game. It's a matching pairs game. It's a homeschooling tool. It's friendly and relaxing. The best way to get kids to practice arithmetic with small numbers and at the same time learn about reasoning, logic and perseverance. 21 Marbles is inspired by the Montessori and Waldorf methodologies, and the Russian Math School. It involves reasoning similar to Sudoku, but with movement and colors that make it engaging even for infants.


- no ads and no in-app purchases

- 21 levels that are different every time you play

- progress can be reset to any previous level

- marble rolling with real physics

- designed for kids but is known to be enjoyed by adults

- appropriate also for a school setting as it doesn't include unwanted distractions and has a very explicit and friendly measure of progress. (e.g. "Have you got a transparent marble yet?")

- attractive marbles motivate kids to continue even when the going gets tough

- has an ending and doesn't try to get you or your child hooked forever; no addiction techniques whatsoever are employed

- two kinds of music - wind and string instruments; the sound and music can be turned off independently

- progress sharing

- practices number bonds

- practices Common Core Standards reasoning

- trains the brain, prevents Alzheimer's
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23 total

What's New

Fix of a glitch in the rating button, and some minor improvements.
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Additional Information

June 25, 2018
Current Version
Requires Android
4.1 and up
Content Rating
Offered By
Balconia Math
Doctor Barraquer, núm.3-5. Sant Sadurní d'Anoia 08770 Spain
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