Is the grammar correct? This is an example of imagery because it appeals to the senses of sight and hearing. Also gives the readers (does there need to be an apostrophe in readers) a detailed description of Mrs. Hirsch's son.
It all sounds fine.
You don't need an apostrophe on "readers" because the readers don't own anything!
**Suggestions and Corrections are in parentheses
This (instead of "this" try identifying what you are talking about; you can write: "This sentence" for instance ) is an example of imagery because it appeals to the senses of sight and hearing. Also (it) gives the readers (no there should not be an apostrophe in readers) a detailed description of Mrs. Hirsch's son. (Overall, good job :) )
The grammar in your statement is mostly correct. However, there are a couple of minor suggestions to improve clarity and correctness.
1. Regarding the first sentence:
"This is an example of imagery because it appeals to the senses of sight and hearing."
The sentence is grammatically correct. However, it would be more concise and clear to say:
"This is an example of imagery as it appeals to the senses of sight and hearing."
2. Regarding the second sentence:
"Also gives the readers (does there need to be an apostrophe in readers) a detailed description of Mrs. Hirsch's son."
The plural form of "reader" does not require an apostrophe. So it should be "readers." However, you could rephrase the sentence to make it clearer:
"It also provides readers with a detailed description of Mrs. Hirsch's son."
So, the improved version of your statement would be:
"This is an example of imagery as it appeals to the senses of sight and hearing. It also provides readers with a detailed description of Mrs. Hirsch's son."