Am I not a good mother??

Both Zach and Morgan got into trouble at school today!! It has been a couple of weeks since I have gotten a phone call from Dr. Lusk, the assistant principal at the middle school. But then again, we have been out of school the last couple of weeks ;[ Regardless, Zach was laughing and disrupting class today and was disrespectful (big surprise) to the teacher. Needless to say, he is suspended from school tomorrow! Then, then, then I got a call from Morgan's teacher saying that she has been behaving terrible all this week! She laughs at the teachers when they tell her what to do (or not to do) like she could care less. What am I going to do with them? Have I been a bad mother? David says that I let Zach get away with too much when he was little. Well, he was sweet then!! Now it seems no matter what we take away from him that it doesn't phase him?? The poor kid has gotten everything taken away from him : playstation, laptop, tv! I think he is so used to being without it because it has been taken away that it doesn't phase him that it is gone. Now, Morgan is another story. She is only in kindergarten so this is all new for her. I never had this problem with her at the daycare/preschool that she has attended since she was 8 weeks old. I'm not sure what to do with her so I decided to punish her by making her go to bed in her own bed without the TV (which is a good idea anyway--but then again that goes back to 'am I am good mother' thing. Hopefully we will have a better day tomorrow. David and I had a long talk with her before sending her right to bed as soon as we got home from dance. Zach will be going to work with David tomorrow--I'm not sure which one is being punished on that one??