Agreed! The private international schools are considered to be good. The facilities are, however, more limited i.e. sports fields, swimming pools etc. than what we had encountered in other parts of the world.
We had decided to settle in the north and only visited IPS and Ecole du Nord (French AEFE school) and also Clavis (in Moka, just below Port Louis). IPS is an accredited International Baccalaureate (IB) primary school - annual fees: starts at around US $ 6300- and non-refundable application fee of $ 1700-. Clavis is also an IB school - appl fee $ 1250- and starts at $ 7700-per annum. There is usually a waiting list at these schools which complicates matters. Our son was already in the French system and he was immediately accepted at Ecole du Nord (starts at around $5500- per annum). It is also includes a high school so that´s sorted.
IPS is a feeder school for Northfields International High School which is situated directly opposite it. It allows students to either follow the IB or Cambridge curriculum. Fees at Northfields start at around $ 12000 per annum.
Not far from there is Lighthouse Primary and Secondary School which follows the Cambridge curriculum. Apparently it is also good. Keep in mind that it is a Christian school. I don´t know their fee structure - available on request.
If you live in the West - around Flic en Flac etc - then West Coast Primary School is also an option. It is an IPC school. Fees are similar to Ecole du Nord.
You may also want to consider Hampton Primary but I don´t have information on it. It is more central, in Quatre Bornes.
Down the road from Clavis Primary in Moka there is Le Bocage International High School which is an IB school. Fees are similar to Northfields High School. These schools are more central but really too far to commute to from the North (IMO).
Keep in mind that these schools do not all follow the same academic calendar.
IPS, Ecole du Nord, Northfields all follow the northern hemisphere academic calendar (end Aug/Sep to June).
West Coast, Clavis and Le Bocage follow the southern hemisphere calendar (Jan to end Nov/December).
All schools have their own uniforms which add to the cost, as do most extra-mural activities.
Given your kids´ages you will probably aim for a combination of IPS & Northfields or Clavis & Le Bocage.
So far our move has worked out well for us. It is never easy but our son has settled in nicely and is enjoying school. It is a good place for kids IMO. We made use of a relocation agent and I would always recommend the same to others - unless they have family here or know the island well.
Traffic is always an issue due to an increase in vehicles on a rather small island. The 13km trip to school in the mornings take us around 30 minutes, half of which is queuing to get into the parking lot! The schools also contract bus services so that is a paid option we will probably consider at a later stage. I do have some reservations about these, given the standard of local driving and the fact that the buses are not equipped with seat belts.
Hope this all helps. Feel free to ask if you need any further information.