The brain undergoes massive renovation during the teenage years. Neural connections are tested and those the brain decides are less useful for your child’s environment are weakened or lost, while the helpful or frequently used ones are strengthened. This process happens in order, beginning at the back of the brain and moving through to the prefrontal cortex, sitting just behind the forehead.
The prefrontal cortex is vital to our ability to think rationally, plan behaviour in accordance with our goals, and analyse risk - yet it’s the last part of the brain to fully mature. In some respects the maturation isn’t complete until our early twenties. This is a really good reason to stay aware and engaged around the big decisions your teenager is making. You can’t think for them, but you do think differently to them, so make sure they benefit from your wisdom when it counts.