I have been in Qatar for about 30 years. Know many families whose kids were enrolled in government schools. Most of them did well coz the families and their kids are keen on being competitive in the labor market. Where as the Qataris are in general not much concerned about competing.

To be more realistic about figures and percentages. I know the Omani experience which I think it is the most successful in "Nationalization" among the GCC.

When the population was about 2 Millions, the expatriates totaled 0.5 M which is a 75% Omanis 25% Expatriates (figures are 10 years old). But looking into the system there, Omanis have to do everything there including Taxi Drivers, Fishermen, PR staff (Non Omanis are not allowed AT ALL for such jobs) and if one walks into a government offices there, will notice at least 95% of the employees are Omanis.