"That was...pretty good! I only tripped once. And I pretty well kept up with you."

Letting the other lead because of course she knows the way around better than Marinette. Given Marinette wasn't exactly local or anything. And she didn't want to race while looking at her phone for the map or whatever. That would have just resulted in her tripping up all the more. So it seemed safer to just keep herself slightly behind the other to let her lead around the school.