Why did some immigrants oppose sending their children to public schools

Many public schools followed cultural assimilation program which was a concern for many immigrants

Explanation:

English language curriculum and American citizenship curriculum were introduced in the public schools which were considered to be important factors for promoting cultural assimilation inn the sphere of education.

Schools were taught not just English but also were focused in completely converting the immigrant into a pure American. If the immigrants refused to follow Americanism, they were sent back to their homes. In order to follow English, many other foreign languages were neglected. By introducing English and restricting foreign languages. There was some commonality that spread in America.