2. How to open a European door after leaving a key in the key hole on the other side. Yeah, doors here are weird and have no knob on the outside of them. They open from the outside only with a key. But if a key is left in the hole on the other side of the door the key doesn't move from the outside. There is no way to open the stinking door at that point without paying a locksmith 100Euro.
6. How to get through grocery shopping with a two year old without tearing my hair out. Oh, you know those large carts we have in America that somewhat keep our children trapped while we run through the aisle, yeah, here we only have tiny ones that don't hold a toddler in the front and are so low to the ground it almost invites them to climb in and out. As if you are giving them a playground while you shop. Not very effective AT ALL!
I'm sure there are many more things I never learned, but we will leave those for another day!