Abstract: A toy comprises a set of building blocks of progressively-decreasing sizes each of hollow configuration and open at its opposite ends. Each block is formed with an outwardly-extending peripheral flange at one end and an inwardly-extending peripheral flange at its opposite end, the dimensions of the blocks and flanges being such as to permit them to be assembled in a configuration wherein the blocks increase in size or in another configuration wherein they decrease in size.

Abstract: A card game comprises a set of cards with each card being formed with a slit along its mid-line starting from one edge and extending for about one-half its width towards its opposite edge such as to permit each card to be inserted via its slit into the slit of each other card in the set to form a pair with one-half of one card aligned with and exposed to view with the other half of the other card. Each card has indicia on each half of the card on opposite sides of its respective slit. The indicia on the half of each card on one side of the slit is non-validly complementary with the indicia on the other half of the card on the other side of its slit, but is validly complementary with the indicia on some, but not all, of the other cards of the set to form a valid card pair therewith when the two cards are inserted into each other via their respective slits.

Abstract: A board game is described comprising a playing board and a set of playing pieces for each player. The playing board is divided into a rectangular matrix of squares having a central undivided rectangular area which is of such dimensions that the spaces between the outer boundaries of the central area and of the matrix squares are occupied by rows of at least two matrix squares. A set of playing pieces is provided for each player, each set including at least three different types of playing pieces carrying markings indicating different strengths relative to each other. Thus, one type indicates "scissors" which is stronger than the second type indicating "paper", which is stronger than the third type indicating "stone", the third type being in turn stronger than the first type (scissors).