The following responses work with any kid in a gang, regardless of why they are there:
1. Find something for this youth to do afterschool. It should be something that he/she can get involved in, make different kinds of friends, and feel good about. This might be a job, a boxing or karate gym, church group, music lessons, dance club, volunteering, or basketball team. The "police explorers" are available in almost all cities and work wonders for kids looking for structure and acknowledgement. Most kids go to jail for crimes committed between 4pm and 9pm. Your son/daughter need to be busy during these hours. And if they don't like school, then they absolutely must be involved in something that will occupy their afterschool hours. Until this kid has something else to identify with and look forward to, the gang will be the only group where he will feel he belongs.
Be strong about this, and don't be afraid to use his probation officer or a local police officer to help you motivate him---the more adults are pushing him in the right direction, the better chance he will go there.
2. Change his or her school and find a smaller one. Gang kids get lost in big schools. They need small places where teachers and counselors can focus on their learning problems, emotional needs, and keep an eye on them. Even if they do not have difficulties with academics, a smaller school will give them greater attention, and give the parent better access.
3. If your son or daughter is on probation, talk to the probation officer and decide together what your children need to do. For example, if you decide that the best way to keep your son or daughter busy is to get a job, then have the probation officer help write a resume, give some ideas, make some phone calls, and prepare him on how to dress and speak. If you think your son/daughter should be volunteering at a local daycare on weekends; or helping the police explorers, playing on a soccer team, going to karate lessons, or helping with a church project---than have the probation officer make this a condition of their probation. I know this sounds a little rough, and your kid will think it is absolutely wroing---but it will save his or her life.
If you can come to agreement with the probation officer, your teenager will know that he/she must keep the job, or stay on the team or keep in the boxing gym as part of their probation. He or she needs to know that you take this seriously, and that the different adults and authorities in his life all have the same idea for him. Kids who are surrounded by strong adults enforcing the same agenda have the best chance of making it out of the inner-city with strong inner-selves.
4. Get others to help: Let the school know what you are trying to do, and get them on your side. Make friends with your son's teachers, counselor and principal. Make sure they all have your phone number and know that you are tyring to find a job or other positive activities for your teenager to get involved in. Respond to their calls, and let the probation officer know right away if there is a problem. The more adults get involved in creating a strong structure, the better the chance your child will cooperate. And the more people on the lookout, the greater the chance that resources will be located. Stay positive with the other adults in your kids life---more flies are caught with honey than vinegar. This is a cliche, but get people on you and your kid's side.
5. Be "all over your son or daughter's life." Go to probation meetings with them; show up at school; don't let them have free time.
"Idle hands are the devils workshop" is an old but accurate saying. The only way to get your kid out of a gang, is to get him into something else. Somehow, you must make put them in activities where they can make different kinds of friends and also develop a different identity beyond the gang. You can't talk a kid out of a gang, or try to lock them in the house. Its never that easy.
6. Finally, you need to join a support group, mother's group, church group for parents---anywhere you can get regular support and a pep talk. You won't be able to do this alone.
The above is not easy, takes time and money, and lots of energy. But if you can't find productive activities for your son or daughter, they will continue to find negative ones easily on the street. And if you can't find something he or she is good at, they will continue to make friends among kids who have nothing going for them. If school doesn't become a place he thinks he can succeed, then he or she will keep trying to escape it. And don't be the lone Ranger----get on the same page with the principal, teachers, probation officer, local police, and anyone else who can help.