"An opportunity for a complete positive transformation of your child for which you have always aspired for".
The above sentence appears on the board of a private primary school. I think the writer has made a redundancy in use of preposition. The sentence should correctly read as follows:
"An opportunity for a complete positive transformation of your child which you have always aspired for."
or:
"An opportunity for a complete positive transformation of your child for which you have always aspired."