How do you say

Our school is organizing a program for an international student exchange for two months.

..in Chinese?

我们学校正在组织一次国际交换生项目,为期两个月.

wǒ men xué xiào zhèng zài zǔ zhī yī cì guó jì jiāo huàn shēng xiàng mù , wéi qī liǎng gè yuè .

How do you say "The weather has been changeable lately, with wide swings in temperature." in Chinese?