The card-game system may include at least one deck of playing cards and one or more sets of rules for playing the educational game(s) using the deck. A deck may include multiple sets of cards. The cards in a first set may relate to a first item that is subject to a cycle, including a number of stages. Cards in a second set may relate to a second item that is subject to a cycle, including a number of stages. Different cards within a set may represent different stages of the cycle for the item of that set. For example, different cards in the first set may relate to different stages of the cycle of the first item and different cards in the second set may relate to different stages of the cycle of the second item. The methods of gameplay may include playing cards based on the sets, the cycles and sequential stages of a cycle within in set. Due in part to this game mechanic, the players get exposed to and ideally learn about the cycles of an item, and the stages and order of the stages of a cycle for that item.