Set-Up
The game comes with a deck 60 Rack-O cards, four Rack-O card racks and one Rack-O card tray. If you are playing with four players, use all 60 cards. For a three-player game, use the cards numbered 1 to 50; and with two players, use only 40 cards. Designate one player as the scorekeeper. Each player receives a card rack to placed in front of him, and the card tray is placed in the middle of the table.
Gameplay
To start a game of Rack-O, shuffle the deck and have each player pull a card from the deck. Whoever has the high card starts the game as the dealer, which rotates after every round. The dealer shuffles the deck again and deals 10 cards -- one at a time -- facedown to each player, including himself. Players pick up each card and put it in their card rack, starting from the back and with the cards facing forward, until the rack is full. The remaining cards in the deck are placed in the card tray facedown; the dealer turns over the top card and places it in the discard section of the card tray. On his turn, a player chooses the top card from either the discard pile or the facedown deck in the tray. If he chooses from the discard pile, he must use that card to replace one of the cards in his tray. If he chooses from the facedown pile, he may immediately discard the drawn card or use it to replace a card in his rack. The card he gets rid of becomes the top card in the discard pile. A player's turn ends when he has discarded.
Scoring
The round comes to an end when a player goes "Rack-O." The player who goes out first scores 75 points -- five points for every card in the rack and 25 bonus points for going out first. The remaining players receive five points for each card they have in their rack that is higher than the card in front. For example, if a player has seven cards that go progressively higher, he receives 35 points.
Variations
When you have only two players, adjust the rules so that a player cannot go "Rack-O" unless he has at least three cards in his rack in consecutive numbered order. Another variation involves playing as partners when you have four people playing the game. Partnering helps the game go much faster, as the partners can pool their scores until they reach 500 points. Scoring remains the same in the partner variation, and the team that wins each round gets additional bonus points if they have perfect, consecutive runs in their racks. A three-card run is worth 50 bonus points; a four-card run is worth 100 bonus points; a five-card run is worth 200 bonus points; and a six-card run is worth 400 bonus points;