Abstract: A psychological test device for measuring the intellectual ability of children by identification of a picture which the examiner exposes in sequential small increments by slowly moving it behind a narrow window. The device comprises a rotatable circular disk interposed between front and back face plates. The front of the disk carries a plurality of pictorial elements. The back face of the disk carries corresponding identifying indicia. A narrow window in the front face plate overlies the path of rotary movement of the pictorial information. A cut-out in one edge of the face plates, coupled with finger notches in the exposed peripheral edge of the disk, permits easy rotation of the disk. A timing scale assists the examiner in regulating the exposure time of each pictorial element being tested.

Abstract: Interlocking educational and recreational blocks in three-dimensional right rectangular form adapted to be connected vertically or laterally to form larger structures. Each block is characterized by a plurality of projecting connecting members on one surface and corresponding mating recessed connecting members on the remaining faces of the block. When precisely manufactured, the interlocking blocks are especially adapted for use in teaching the metric system and other mathematical concepts to school children and others.

Abstract: A presentation folder for the display of test or other educational material or sales or promotion material, or the like. The device is a compact unit for storing and displaying pictorial and/or typographical material printed or otherwise reproduced on pages within the device. When closed, it is in the form of a book. When opened, it assumes the form of an easel presenting stimulus material. The unit includes a one-piece molded casing having relatively stiff front and back covers formed integral with and hinged to a spine, and includes a plurality of pages of pictorial and/or typographical stimulus material loosely bound, as by spiral or other binding, or the like, for flipping from one side to the other of the easel formed when the device is opened. The device is provided with an integral storage compartment for receiving manuals, recorded tape reels and/or casettes, or the like.