This sounds innocent, but is actually a very thorny issue. Of course, it's not such a good deal when you reach retirement age and find that you haven't built up the pension fund that you always intended to. The school may give you the money and call it a pension plan, but it really isn't. U nless you work in a country with a tax treaty with the US wherein they recognize each other's Social Security or equivalent, the vast majority of programs among international schools either violates IRS rulings on taxation or sets you up for a massive tax penalty when you withdraw your pension money.
T hat's a harsh statement.
It's unfortunately true. A school contribution into a foreign registered and administered fund may NOT be included as part of your Form 2555 Foreign Earned Income Exclusion. That's the second booklet that the IRS sends you with your Form 1040 in the overseas tax package. The legal reference, for those so inclined, is Section 911 of the Tax Code. The salesman no doubt told a good story of how these areas charge no income tax, the funds grow tax-free, and the fund management reports to no national tax authority.