Constructive assembly comprising separate assembly parts

A construction assembly made up of a plurality of connected assembly parts comprising:

• a plurality of separate assembly parts, each of which is buoyant and has a positive meta center height, comprising a first side provided with at least one side projection projecting outwardly from a surface defined by said first side, a second side parallel to said first side which defines a second surface which defines at least one side recess which is depressed from said second surface, each of said at least one side projections and each of said at least one side recesses being shaped such that a side projection of a first assembly part can be releasably gripped by a side recess of a second assembly part which is positioned next to said first assembly part when at least one of said first and second assembly parts is tilted and said side projection is inserted into said side recess, and a top face having top face margins at least some of which define at least one locking recess with a closed end and an open end such that when said first and second assembly parts are assembled a first open end of a locking recess of said first assembly part will be aligned with a second open end of a second locking recess of said second assembly part;
• and
• a releasable coupling element shaped to substantially correspond to the space defined by said first and second locking recesses when aligned, said releasable coupling element to be positioned within said first and second locking recesses when aligned thereby affixing said first assembly part to said second assembly part.