A trigonometric function display clock includes a clock face that has a center aligned with a central axis, axial markings aligned with an x-axis and a y-axis, and a secondary circle having a diameter equal to a radius of the axial markings. A first point on the secondary circle is aligned at the center of the central axis, and the secondary circle is configured to be rotatable about the first point. The secondary circle is configured to overlap and align with at least a portion of the axial markings as the secondary circle rotates about the first point.

A construction teaching set for education. A polyhedral block body has first and second divided members and provided by engaging and assembling of the first and second divided members. Each of the first and second divided members has a rectangular plane, a plurality of rectangular inclined surfaces adjoining sides of the rectangular plane, triangular connectors formed between the adjacent rectangular inclined surfaces, and a plurality of vertical skirts extending from the plurality of rectangular inclined surfaces and the triangular connectors. A connection bar has a protruding fastener at one end or both ends to be selectively connected to one among a first fastening hole passing through the rectangular plane, second fastening holes passing through the plurality of rectangular inclined surfaces, and third fastening holes formed in a pair of the vertical skirts adjoining each other. A coupling unit generates coupling force for the first and second divided members.

An educational apparatus is disclosed. The educational apparatus has one or more first sheet members including a first side and a second side, the first side and the second side each having first markings indicating the same first surface area, and one or more first attachment portions disposed along some or substantially all of a perimeter of the one or more first sheet members. The educational apparatus also has one or more second sheet members including a first side and a second side, the first side and the second side each having second markings indicating the same second surface area, and one or more second attachment portions disposed along some or substantially all of a perimeter of the one or more second sheet members.

An educational apparatus is disclosed. The educational apparatus has one or more first sheet members including a first side and a second side, the first side and the second side each having first markings indicating the same first surface area, and one or more first attachment portions disposed along some or substantially all of a perimeter of the one or more first sheet members. The educational apparatus also has one or more second sheet members including a first side and a second side, the first side and the second side each having second markings indicating the same second surface area, and one or more second attachment portions disposed along some or substantially all of a perimeter of the one or more second sheet members.

A trigonometric function display clock includes a clock face that has a center aligned with a central axis, axial markings aligned with an x-axis and a y-axis, and a secondary circle having a diameter equal to a radius of the axial markings. A first point on the secondary circle is aligned at the center of the central axis, and the secondary circle is configured to be rotatable about the first point. The secondary circle is configured to overlap and align with at least a portion of the axial markings as the secondary circle rotates about the first point.

A trigonometric function display clock includes a clock face that has a center aligned with a central axis, axial markings aligned with an x-axis and a y-axis, and a secondary circle having a diameter equal to a radius of the axial markings. A first point on the secondary circle is aligned at the center of the central axis, and the secondary circle is configured to be rotatable about the first point. The secondary circle is configured to overlap and align with at least a portion of the axial markings as the secondary circle rotates about the first point.

A method and system for using a natural language generator for automatic assessment item generation is disclosed. The natural language generator includes a document structure generator that produces an abstract document specification defining a structure for an assessment item based on user input. The abstract document specification is input into a logical schema generator, which produces a logical schema specification that creates a more detailed specification for an assessment item. Finally, a sentence generator receives the logical schema specification and creates natural language for the assessment item based on the variables defined in the logical schema specification.

A method and system for using a natural language generator for automatic assessment item generation is disclosed. The natural language generator includes a document structure generator that produces an abstract document specification defining a structure for an assessment item based on user input. The abstract document specification is input into a logical schema generator, which produces a logical schema specification that creates a more detailed specification for an assessment item. Finally, a sentence generator receives the logical schema specification and creates natural language for the assessment item based on the variables defined in the logical schema specification.

Shape-matrix geometric instruments having numerous applications including, but not limited to, anti-counterfeiting, graphical passwording, games, and geometry education. A shape-matrix geometric instrument is a manufacture and/or a method whose design is based on a shape-matrix that, in turn comprises a set of building blocks that are N-dimensional polytopes. Corner shapes are positioned in or near the interior corner spaces of at least ones of the shape-matrix building blocks. At least ones of the corner shapes differ from others in at least one property or aspect including, for example, geometric shape, orientation within the building block, and one or more surface finishes, such as color, shading, cross-hatching or real or apparent texture.

Shape-matrix geometric instruments having numerous applications including, but not limited to, anti-counterfeiting, graphical passwording, games, and geometry education. A shape-matrix geometric instrument is a manufacture and/or a method whose design is based on a shape-matrix that, in turn comprises a set of building blocks that are N-dimensional polytopes. Corner shapes are positioned in or near the interior corner spaces of at least ones of the shape-matrix building blocks. At least ones of the corner shapes differ from others in at least one property or aspect including, for example, geometric shape, orientation within the building block, and one or more surface finishes, such as color, shading, cross-hatching or real or apparent texture.