agree in ...?

[coteti]

Is it correct to say " I agree in that children used to play a lot more in the past?" or would it be better to say " I agree with the fact that children used to play a lot more in the past".
Thanks in advance for your help!

[mykwyner]

I agree that children...
I agree with the fact that children...
I agree, in part, that children...
I agree, on the one hand, that children...

These are some common ways that native English speakers would start a sentence such as yours.

[RonBee]

Absent context (and a reason to choose something else), "I agree that children used to play a lot more in the past" is simplest and best. (I wouldn't use "the fact that" unless somebody was holding a gun to my head.)

[David L.]

People are having a discussion, and one says, "Children had better social skills in the past than now, and I think it's because these days, children spend too much time on their own huddled at a computer."
Someone else then says: "I agree, in so far/to the extent that children used to play (together) a lot more in the past, but I can't agree that...."