The in-game help screen explains the scoring rules. Here's a quick summary of how it works.

• Each turn, you get to roll the dice up to 3 times and then lock in your score onto a cell on the sheet. Each cell can be used once and the game ends when all cells have been used.
• Each row has its own scoring rules to determine the base value (see below for more information).
• You can select the x1, x2, or x3 multiplier cell. 
• If all 5 dice rolled are showing the same color, you get a choice of rolling the multiplier die at the cost of any remaining re-rolls. The multiplier die can give you nothing, x2, or x3 additional multiplier.

Scoring rules per row:

• ONES = Add up all the 1s on your dice
• TWOS = Add up all the 2s on your dice
• THREES = Add up all the 3s on your dice
• FOURS = Add up all the 4s on your dice
• FIVES = Add up all the 5s on your dice
• SIXES = Add up all the 6s on your dice
• 3 OF A KIND = Add up all the dice if at least 3 are of the same value
• 4 OF A KIND = Add up all the dice if at least 4 are of the same value
• 5 OF A KIND = 50 points if all dice are of the same value
• FULL HOUSE = 25 points if you have both 3 of a kind and two more dice of the same value
• SMALL STRAIGHT = 30 points if dice show four consecutive values
• STRAIGHT = 40 points if all dice show five consecutive values
• CHANCE = Add up the sum of all dice, the higher the better

Maximum points: