THE boss of education technology specialist Promethean World is leaving the business to pursue a new challenge, it has been announced. Jean-Yves Charlier, the US-based chief executive of the Blackburn classroom interactive whiteboard supplier, revealed his  intention to quit as the company revealed half year operating losses of £148.5m, compared with a profit of £4.1m a year ago.   The bulk of the loss related to a goodwill write-off of £140.5m, adjusted ebitda was a loss of £300,000 compar......for the full story register now for free or login below...