This is one of the best educational sets produced by LEGO in the Dacta/Education line!
It is well-designed in many ways, from the storage box itself (with a self-organizing plastic tray) to the instruction booklets (which are truly inquiry-based learning exercises, yet still language-independent). The booklets (projects/lessons) introduce mechanical design concepts from simple to complex machines, gradually building in complexity as one works through the projects. The projects are common mechanisms, such as a folding lawn chair or a conveyor belt, for which one gets to build and see the inner workings. The set includes many "Technic" parts that can be reused for many additional creative projects when the ideas from the booklets are applied.
The modern analog is set 9686 (Simple & Powered Machines Set); not as well designed IMHO but still fun and worth acquiring for classroom or home learning.
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