Yes, but #4 is unnecessarily wordy.
Rover

Academic
-You know Jim Smith, right? He is related to your wife.
1-Yes, I was also classmates with him.
2-Yes, I was classmates with him as well.
3-Yes, I was classmates with him too.
4-Yes, there is also the fact that I was classmates with him.
Are sentences 1-4 all acceptable in this context?
Gratefully,
Navi.
Yes, but #4 is unnecessarily wordy.
Rover