@Shamar Your sevens may be or seem smarter than others, it's possible, try to force their cognitive schema by presenting two objects belonging to the same class, for example, a truck and a car or tree and fruit (this more problematic). See how well they are able to abstract from a particular concept to a general one and to the decomposition of the objects itself. The problem is that they might “understand” in first, but forget shortly if their cognitive schema is not sufficient.
I wonder how much abstraction we need to program in C (or in Oberon without inheritance)...
@Shamar That's not the problem: C, Oberon or any programming language. The issue is whether it's appropriate or not. If kid will not benefit from it because he's unable to benefit from it, is it really needed? Why not to give him canvas and brushes for painting? In order to get knowledge, it's necessary to challenge the actual cognitive schema, but thanks of the previous one that the following is accommodated and consolidated.
@Shamar For that stimulus the school goes (should) advance by degrees and thorough repetitions of the same thing. Each time the schema is challenged and overcome. Adult man should do it by himself, although very often he fails miserably. :D
@Shamar At that age (seven) the capacity for abstraction is still minimal. To begin to understand cognitive theory you can read, in first, Piaget and Vygotsky theories and for example find the differences and similarities. Regardless of certain differences they identify stages (Piaget for ages more defined, Vygotsky more related to socio-linguistic interaction).