Hi Jess, I feel for you Angel was one of those kids it seemed any form of discipline (even rewards) didn't work. Remember one time turned her TV off and told her "no TV until you start cleaning" in the blink of an eye I had a 19inch TV flying at me, window broken and she was out of the house for around 6 hours that time. An hour after she split when we couldn't find her the police put out the amber alert, she was found on a garage roof down the street (a neighbor saw her watching the search and called in her location).
Ross Greene's basket approach works great with 5-6 yo's but 15yo's? I doubt it at least not by itself. I ended up using bits & pieces of everything in my parenting arsenal to develop what worked for my kids. Classes Love & Logic, STEP & Oregon parent management training; Ross Greene's basket approach, out of sync child (can't remember author), most of my ammo came from a couple books by Amy Sutherland (kicked, bitten & scratched; What Shamu taught me about...) if those titles not familiar in parenting it's because they are about training exotic animals... LOL actually how Amy used techniques for training animals to train her husband then went on to use it with everyone she interacted with.
It comes down to reward the behavior you like and ignore the ones you don't. Also uses incompatible behaviors - like her husband would get in her way while cooking (felt like she was tripping over him or asking him to move constantly) so when she wanted him out of her workspace she would put chips & salsa at end of counter and he would naturally go to the area she had directed him into without knowing he was being trained. With kids you have to modify it because you can never ignore what is considered assault.
We got so use to Angel assaulting us we got lazy about punishing every incidence, so in her mind it became acceptable behavior. When she would get frustrated at school they absolutely wouldn't tolerate it and it cost her getting an education and social isolation in a Special Education school that was equivalent to juvi where you go home to sleep. Expelled from public school at age 12 and it took till she was 17yo to work thru all the levels at the day treatment school to get go back to public. I got a 19yo with no diploma, friends or social skills.
Sexting is a problem but not as bad as when phone has a camera; a 15yo boy would think it was funny to send a picture of his "junk" to a friend but sending nude photo's of a 15yo is a felony. Kids unsupervised on the internet is flat out dangerous, my 17yo has given out our land line phone number to many "friends" she's met online... She just doesn't get it!!! they exchange phone #'s, calls they get last name off caller ID can open phonebook or internet search and they got our address, use to be could google a phone # and it would give driving directions to the location of that phone.
Like I said I understand what you are going thru and you are not alone, many of our kids don't respond properly to traditional dicipline and parents need to modify their approach.
Nancy