A model air rocket assembly includes a finless cylindrical body of substantially uniform diameter. The assembly comprises a nose cone, an intermediate canister tube and a lower body tube. The engine is positioned in an engine tube held concentrically within the canister tube. The engine tube extends down to approximately the lower edge of the canister tube and openings are arranged around the lower portion of the canister tube to admit air which augments the engine thrust through the body tube a...

The model airplane is of the type formed of a thin sheet of plastic material. A propeller assembly including an engine-noise-simulating member is mounted at the forward end of the airplane. The propeller assembly is connected to a rubber band which is secured within the fuselage of the airplane and extends from the forward end thereof. The noise-simulating member is releasably mounted on the propeller assembly and includes a portion which extends into the path of rotary movement of the propeller...

A model airplane having a pivotable wing for imparting superior aerodynamic performance characteristics. Wings are folded toward fuselage during airplane launch and automatically extended outwardly during flight to provide airplane lift surfaces for a gliding descent.

A jaw model for teaching and instruction purposes has at least one insert mounted in a recess of a mandibular arch. The insert is elongated in one dimension, and is movable into a functional position by rotation about a socket pin which is oriented substantially perpendicular to the elongated dimension of the insert. The socket pin is rotatably mounted, and within predetermined limits, longitudinally movable in a guide hole provided in a tongue or gum part of the jaw model.

A device for accelerating model vehicles comprises a track portion movable relative to a base part by resilient means. The track portion is held in a cocked position by a trigger mechanism and is released when a vehicle entering the track portion from an incoming track trips the trigger mechanism. A movable barrier, displaced by the entering vehicle falls back behind the vehicle to accelerate the vehicle as the track portion is accelerated by the resilient means. The track portion may be movable...

An anatomical model comprises a simulated main body blood vessel having a predetermined curvature at a portion thereof and is formed of a yieldable plastic material. At least one simulated secondary blood vessel is interconnected with the main body blood vessel at the curved portion. Means mount the model and comprise means for varying the positioning of the secondary blood vessel with respect to the main body blood vessel to correspond with variations caused by aging or abnormalities in natural...

A model for representing nucleic acid molecules, such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) consists of a plurality of helical segments secured together in end to end relation in the form of one or two helixes comprising the molecular backbone. Each of the helical segments is proportioned in length and helical curvature to be a model of the backbone units of the DNA and RNA molecules. Each unit has a flat planar member extending from the mid portion thereof which has a shape ...

A teaching aid which has a display board and a number of discs having symbols printed thereon and magnets for attaching the discs to the display board. The teaching aid is particularly directed towards the teaching of chemistry and the discs have printed thereon atomic or ionic symbols and can be so used to display the theory of chemical bonding or construction of a nucleus.

A model figure of an animal which can be caused to perform a forward walking movement or like forward travelling motion by the application of finger or other manual pressure to the head of the model animal. The model basically comprises a first member (1) which includes an upper jaw and two fore limbs, and a second member (12) which includes a lower jaw, a body and at least one hind limb, the two members being pivotally interconnected by a pin (10) or the like which is situated at, or substantia...

A model airplane comprises a flat wing and a member connected to the wing midway between the wing-tips and near the back of the wing which extends away from the top surface of the wing. A freewheeling vane is connected to the back of the member and spaced-apart from the top surface of the wing.