Board games are a celebration of problem solving, and problem solving is at the heart of a quality mathematics education… The mathematics might be hidden, but I guarantee you that it will be there.
— Gordon Hamilton, MathPickle.com
Commercial Games 8
Denise Gaskins' Let's Play Math 
I love the 8+ video and recommendations but the 12+ has a link to the 8+ video.
Oops! Thank you for pointing that out. My internet connection was running so slow that I didn’t take time to double-check the post. I should have known better. Fixed now.
Any recommendations for the 6-8 age range please?
cheers
We have found that most games that an 8 year old can play can also be played by my 6 year old. If you’re unsure, try playing on a team with your 6 year old and let them do as much on their own as they can – they may surprise you!
One game that is actually rated 6+ that we enjoy is Qwirkle.
Have used many games in the classroom. One worth your site mentioning is Mathopoly, which comes out of Canada. I ordered it online (mathopoly.ca) Amazing for ages 12 and up, some of my students parents are using it to brush up on their own skills too. Thanks for the great site.