What is the indirect object in Priests living at castle taught rich children reading and writing?

The indirect object in the sentence "Priests living at the castle taught rich children reading and writing" is rich children.

Here's why:

* Direct Object: The direct object is the thing that is being acted upon by the verb. In this case, the priests taught *reading and writing*.

* Indirect Object: The indirect object is the recipient of the direct object. The priests taught *reading and writing* to the *rich children*.

So, the rich children are the ones receiving the benefit of the teaching.