This game uses double-6 dominoes to practice simple addition for young children. But it’s also a great strategy game for players of any age.
“Domino Bond” is an excerpt from Math You Can Play Combo: Number Games for Young Learners, which is available as an ebook at my publisher’s store (where you get all formats for one low price, and I earn higher no-middleman royalties) or through other online retailers, or by special request through your local library. Read more about my playful math books here.
The Math Game Monday posts will be available for one week only. If you missed this one, explore the links in the sidebar. There are more than forty free games scattered around the blog. Have fun playing math with your kids!
Denise Gaskins' Let's Play Math 
First variation I’m wondering: why not play off both ends of doubles? More numbers to look at and number pairs to consider. Second thought: Could do the exact same game for sums to 12 maybe? Probably need to add branches where you could play one end of tile perpendicular to a previous. Got to go get the dominoes out…
Traditional dominoes (at least, the way I learned the game) doesn’t play off both ends of the doubles, so I kept that in the rules. I think it’s to make strategic play possible, because you can guess at what the other player has based on the tiles already played. With only two live ends on the train, you can trap the other into not being able to play, but that gets harder as you add more live tiles.
I’ve seen double-15 domino sets. Or you could play to a sum of twelve with a double-9 set if you removed the low numbers.