Is the wife's return with her children to her Arab country, in order to preserve the Arabic language and religion, considered disobedience to the will of her deceased husband who enjoined her to educate them with "the best education" in America?

It is permissible for the wife to return with her children to her country to preserve their language and religion. This does not contradict their father's will; rather, it is considered an amendment to the will, because learning the language of the Qur'an and matters of religion is among the most emphasized types of education. This is supported by Allah Almighty's saying: "But if one fears from the testator some error or sin, and he amends thereby, there is no sin upon him. Indeed, Allah is Forgiving and Merciful." (Al-Baqarah: 182).