It's not unusual for saplings to have unusually large new leaves.  There are varying opinions on why it happens, but it's a normal occurrence. If your tree is in part shade, it could be that your little sapling is growing larger leaves to capture all the sunlight it can to make plant sugars and feed its roots. Please do not cut them off--you will damage the leader of your tree.  If your trees are in a windy place over the winter, you may want to stake them, but I don't recommend it.  Staked trees just don't grow as strong--they need the wind to help.