Recently Modified Leads report??

What exactly do you have to do to a lead to have it appear in this report?
or what can I use to do the following

I have an off site sales person. I am trying to track things they are adding - specifically notes into leads files.
I though that adding a note to a lead would be enough to have it appear in the "Recently Modified" lead report, but it is not.

It seems like lead updates would be what I'm looking for.
But I don't see a way to make a view out of that

any ideas?