When children are babies the gap between the developmental milestones is narrow, all easily learnt about through a small 3 or 6 monthly time-frame. As our children grow that gap grows from months to years which can make it difficult for parents to understand why certain behaviours occur.
11-13 year olds (read more on this here) are developing their social and emotional development at a rapid rate so these years can be fraught with moods, chatting back to parents, irritability and being mean and/or having peers be mean to them.
It's easy to forget that their brains are no where near fully developed yet, there is so much wiring and fine tuning happening in these years that it's inevitable (just as with a toddler) that they will be fraught with tears and arguments. Add hormones into that pot as well and you can have yourself an interesting time.
Because the margins for development are so much wider it can make school particularly difficult as children are mixing by age not stage, and that's a whole lot of developing and different stages happening in one classroom.
Keeping this development at the forefront of our minds helps us to stay compassionate when dealing with children in this age bracket; after all they are developing their social and emotional skills so modelling to them how you want them to be is critical for their development.
Using emotional literacy skills at ALL stages is vital for both your own sanity as well as your child's development. It can maintain your relationship even when you're both feeling upset or angry with each other.
Be reassured that you are not raising a 'devils child' you're doing a fabulous job and just like any stage of development there will be calm again; we just have to facilitate the storm passing.