How to Play: Spades
How to play: In this game, spades are the highest value of all cards. The point of the game is to win the number of tricks, or hands, that your team bids for by having the highest card. Players divide up into teams of two and cards are dealt so each player has 13 cards. Looking at your cards, you want to make a bid as to how many tricks you think you can win. You can bid nil, or blind nil, if you don't think you'll win any tricks throughout the hand. It is a good idea to keep track of all bids by writing them down. The player who has the two of clubs plays that card first, and then play continues clockwise. You want to play your lowest clubs card. If you don't have a club, play a heart or a diamond. Whoever won the trick will play first. If that's you, play any card except a spade. You want to follow suit as close as possible, holding your spades back, if you can. Play an entire round, which is 13 tricks, until all of the players are out of cards.
The rules: The team that made the same number of tricks as they had bids, scores 10 times the bid for the total team bid. Plus, they get an extra point for the additional tricks that they played -- this is called sandbag. If there was a successful nil bidder, the team gets 50 points. You also will include the score of the partner's tricks, whether that's winning or losing. A successful blind nil wins 100 points plus the score of the partner. You will deduct 10 points for every trick that the team won that wasn't bid on. Basically, for extra tricks, minus 10 points each trick. Add in the score that was won or lost by your partner. Deduct 100 points for a failed blind nil bid, and add points won or lost by the partner.
How to win: The team that reaches 500 points first wins.
What else you need to know: There are many variations to Spades, and Pagat has a good resource for all the variations and different rules for Spades.
Related: More Kids Games
Start by teaching him that it is safe to do so.