Is the usage of me and I correct in the following sentences? If not, what would be the correct way to say these sentences?

1. I wish I had known about these picture board systems then, as it may have enhanced the communication between the children and me.

2. It was frustrating for both the child and I, as I had to figure out what the child wanted.

1. is correct.

2. is wrong.

The "child and me" are objects of the preposition "for." A quick way to determine the right pronoun is to omit the noun.

for I?
for me?

In both sentences, the usage of "me" and "I" is not correct. The correct pronouns to use in these sentences are "me" and "myself." Here's the corrected version of each sentence:

1. I wish I had known about these picture board systems then, as it may have enhanced the communication between the children and me.

Explanation: When referring to yourself as the object (the recipient of the action), you should use "me." "Me" is the objective case pronoun. So, in this sentence, since you are talking about the communication between the children and yourself, "me" is the correct choice.

2. It was frustrating for both the child and me, as I had to figure out what the child wanted.

Explanation: Again, when referring to yourself as the object, you should use "me." However, in this sentence, you can also use the reflexive pronoun "myself" as an alternative. So, the corrected sentence would be "It was frustrating for both the child and me" or "It was frustrating for both the child and myself," depending on your preference.