I am a stepmother of an 18 and 17 yr old. I realize that they could have much worse behavioral problems but I am so sick and tired of them not putting their dirty dishes in the dishwasher, missing the bus unless I chase them, then I have to drive them, them not doing their few chores we ask them to do unless we constantly harp, not keeping their grades up and then having excuses as to why it's not their fault.My stepdaughter, now that she has turned 18 is acting like she's running the house - changing the way things are done, taking the mailbox key to make "her own" copy and then losing the key. And then we get criticized because we aren't acting like cheerleaders - being endlessly interested in what they're interested in, and giving an endless stream of positive comments - when we're not happy with how they are behaving.I am becoming more and more resentful and over the last year I have become more and more distant with them. I just feel like we are "hunkering down" to get through these last years 'til they move away. We have tried talking but it doesn't seem to do any good. Is it too much to expect at their ages, that they make good grades, make the bus, do their few chores and pick up after themselves?It would probably help you to join a support or educational group for parents of teenagers. So much of the behavior you describe is just normal adolescent behavior, but it's creating more conflict than it needs to, perhaps because you don't understand adolescence.The teen years, especially the late teens, are the years in which a kid prepares for being an adult in the world alone. So nature gives kids this huge developmental push to be in charge of their own lives at this age, and they start to react against anyone telling them what to do, even if the thing they're told to do is good for them.It helps to ask yourself "Who owns the problem? Which problems are family problems, which are your problems, and which are those of the kids. The only problems you need to be involved in are the ones which affect you or the family. The other problems need to be left with the kids. I'm going to go through the rest of your letter and comment on each particular problem.* I am so sick and tired of them not putting their dirty dishes in the dishwasher,Okay, this one is a family problem because it affects you. But you don't want to be nagging all the time. So how about making a deal - you will stop nagging about this and other things if they clean up after themselves without being asked? When a parent harps, it just teaches the child to tune her out, and to not do anything without being nagged.* missing the bus unless I chase them, then I have to drive them,This is definitely the kids' own problem, not yours. Let them know that you won't chase them to get ready, and you won't drive them. They have to get themselves to school from now on. Don't wake them, don't nag them, don't do anything, just ignore them when they're getting ready to go to school or anywhere else.* them not doing their few chores we ask them to do unless we constantly harp,This is a family problem. But with kids of this age, chores shouldn't be assigned, they should be negotiated. Meet with the kids and ask them what chores they are willing to do on a weekly basis. If they participate in choosing the chores, they're more likely to do them. Have them agree on a time when the chores must be completed by. Then quit nagging! Just leave it until the time agreed upon. And perhaps in the agreement, the kids would be willing to agree that they can't go out until the chores are done on that particular day.* not keeping their grades up and then having excuses as to why it's not their fault.This is not your problem, it is theirs. What are these kids going to do after they leave home and go to college or have jobs? Will someone be there to tell them to do their homework or get to work on time? No! So they need to learn to tell themselves these things, not have you tell them. That's why they need you and their father to get "off their back" about their grades. They will learn far more from failing a course than they will from you always trying to prevent that. Let them know that from now on their grades are their business and you will back off.* My stepdaughter, now that she has turned 18 is acting like she's running the house - changing the way things are done, taking the mailbox key to make "her own" copy and then losing the key.It sounds fairly reponsible to make her own copy of a key. And if she loses it, she learns because she now has to make another copy at her own expense. Her "running the house" is her preparing to live independently. The same with changing the way things are done. Allow her to have some input into family decisions which affect her. This is important for her development as well as for her feeling cared for.* And then we get criticized because we aren't acting like cheerleaders - being endlessly interested in what they're interested in, and giving an endless stream of positive comments - when we're not happy with how they are behaving.You really do need to step out of the power struggle, and be responsible for your own life and not for theirs. Then applaud their own efforts to be responsible, like when they manage to get ready for the bus in time, or when they get a good grade. And when they don't make it, just be sympathetic - "Oh, darn, you missed the bus again. I hope you don't get into too much trouble for being late." "It must feel silly to have such a bad grade when you know you're smarter than that. I bet you can get your grades up if you want." But don't judge or nag, and let their business continue to be their business, not yours.* I am becoming more and more resentful and over the last year I have become more and more distant with them. I just feel like we are "hunkering down" to get through these last years 'til they move away.You may be responding here to the way the kids feel. Many older teens are just waiting to move out of the house and do things their own way. They don't realize it's the last time they'll actually have living with you. Treasure these years they're the last you'll have too. One day, believe me, you'll actually miss the mess!I think if you let go of the problems that aren't yours (getting them to the bus, getting good grades) you'll feel less resentful, and the kids will start to learn from their own mistakes. Good luck!