A Lying teenager

I have a 14 year old daughter. My daughter, within the last 2 weeks, has been lying terribly. She took a cellphone that was left on the bus by a boy. She went to visit her grandmother which is my mother-in-law. My mother-in-law called me and asked me if I purchased another cellphone. My daughter kept giving her different answers on where she got it. I asked her and the first answer was from a girl at church. Another answer was that she got it from a girl at her lunch period in school. She kept giving different answers. It frustrates me so much. This was last weekend. I am a Christian and my mother-in-law and I have made her write the 10 commandments to not lie. She asked us to forgive her. Well, I caught her in another big lie today. I don't even want to look at her. I can't even trust her anymore.
I don't know how to deal with this or how to disipline her.
It just makes me so MAD. She is a wonderful girl and has never been in trouble until now. We have a wonderful family, no problems. Wonderful grandparents on both of my parents side and my husbands side who spoil my kids rotten. She has plenty of friends and is making good grades in school. I don't know why this is starting to happen. Please tell me what I should do. I am now at the end of my rope!!! How do you stop a teenager from lying!!

[misled 1]

u sure this just stated  or just caught it  I find kids behavior by 14 was developed earlier   if just a small lie   ibrushed my teeth  i had a 3rd grader intercepting her report cards  great kid    but constantly lied until i continued to tell her she wanted to be a pre teen to adult and be trusted    be grown and tell the truth  well that was   .......... years ago  she is 18 now grad in colleg  and we laugh about the lying   keeep talking  it may be YOUR  trust she is looking for..   Have you told her to tell some one u not home when she answer the phone??

[Sunshine912]

No, I have not told her tell people I am not home when I am.  She used to tell her sister that  lying was wrong. When my girls fight, my 14 year old used to tell me that I should not listen to my 11yr old becuase she lies. I would say that my 14yr old made such a big deal about it that it comes as a shock to me to hear her telling lies.

[anxiousmomtobe?]

Be firm, give consequences when you catch her in a lie, praise her when she tells the truth in a difficult situation (ie something that if she owns up to will get her trouble).

Grade 8 is the worst year for girls.  My daughter drove me mad that year.  She is now in grade 10 and is really becoming a wonderful young woman.

[RockRose]

Oops,  "good thing I like grey hair.  "   ;D

[RockRose]

Sunshine - is it possible that the boy didn't actually leave his cell phone on the bus,  but that she stole it out of a backpack or locker,  or other place?

You don't say what the other "big" lie you caught her in was,  but at this age she can really be up to a LOT of no-good,  and you may not have any evidence except this attempt right now to cover her tracks.  

In my experience with teenagers,  lies often cover up a worse behavior than you even think you've discovered.  

If you have a way to read her cell phone text messages,  or on-line IMing,  or overhearing her phone calls,  I think you should.  If it turns out that she actually DID just find a cell phone and wanted to keep it so she fibbed about where it came from,  that's a relief.

Best wishes.  Whoo,  teenagers.   Good think Iike grey hair.  ;D

[Sunshine912]

I have took away everything that she likes. I am being very firm. The sad thing though is that I really don't want to be around her and when she tells me something, I tell her I don't want to hear her because I don't believe a word she says. I just wrote the school counselor and made her aware of what is going on. My daughter has ADHD and she is on medication for seizures. I am scared because my daughter has never been able to distinguish between right and wrong. She has never been concerned of what consequences occur when she does something wrong. I would love to take her out of middle school and home school her but my husband wont have it and I wondering if that would even be the answer to the problem.

[tawnya123]

I have a 12 year old boy wiht Autism and he has been lying. He has been writing innappropriate stuff. I need encouragement. I get so mad.