"Educational subject" (versus "empirical subject") would be neater, but I am rather doubtful whether it would work in English; I would stick with "of education".

But for "sujeto", I think there is no alternative to "subject". The term comes with such an enormous amount of intellectual baggage that it is really inescapable. There could be a problem of ambiguity with "subject" as "them" or "topic", but in this context there won't be: "Who is the subject of education" will make it quite clear that we are talking about the subject as the individual, in terms of the vast modern philosophical literature on subjectivity. The reference to "empirical subject" shows very clearly that we are in this world.

You say this is an "abstract". It looks like an academic essay, and it should use the appropriate language. "The subject" is everywhere in modern academic discourse.

Tina Besley and Michael A. Peters, Subjectivity & truth: Foucault, education, and the culture of self:
"What and who is the subject of education and what are the forms of self-constitution?"
http://books.google.es/books/about/Subjectivity_truth.html?i...

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Note added at 18 mins (2011-11-14 18:08:14 GMT)
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"The central curriculum fact is the life of the individual who is the subject of education. De-centring the teacher's voice to allow the voices of others as a focal presence in the construction of curricula is a pre-requisite of educational action that allows relationships of teaching to take place."
http://www.enquirylearning.net/ELU/Issues/Education/Ed3.html


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Note added at 23 mins (2011-11-14 18:12:44 GMT)
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"The human person is the subject of education: he is a human person learning and being taught. The human person is also the object: the human person is at the center of the curriculum and the entire program."
http://www.valueseducation.net/vep.htm

"The modern individual is the subject of education. When we think of education, we think of educating the individual, even though people are taught in groups"
Roger Mourad, Jr., "Education after Foucault: The Question of Civility"
http://inkido.indiana.edu/research/onlinemanu/papers/focault...