Dealing with stubborn absent minded tween

My 6th grader is stubborn and also very absent minded. The problem we run into is she repeatedly forgets things (leaves stuff behind, loses things, misplaces items, etc.) but then insists she did not or blames someone else.

For example, she got a new expensive jacket for Christmas. I told her to make sure she wore it to school with the cold weather and then said – well it is in daddy’s car, he never took it out. Knowing that I used that car the day before and she was in the back seat and also we had used the trunk it could not possibly be there. I then found it where it should be. Not just us – but her teacher told me she asked my daughter for her homework and she insisted she passed it in. The teacher double-checked it wasn’t there, so the teacher looked through her folder and there it was.

It happens repeatedly. She insists such and such and is very adamant about it, but then I or someone else finds an item elsewhere. I have pointed out how she does this often and how easy and normal it can be to forget, that she should be open minded and look thoroughly. I also tell her before we leave anywhere – to check around her and make sure she has everything.

She has been lucky – once she left her iPhone in the bathroom, blamed me saying she handed it me, and fortunately someone turned it in. Usually it isn’t big items like Iphones (she is good about those) just her insistent stubbornness that it is someone else’s fault.