There are two types of meningitis vaccines - if your child has already had the MenACWY vaccine (recommended around age 11-12), then they're covered for the most common types of meningitis. MenB is scary, but it's much more of a danger for those who are immunocompromised or on immunosuppressant drugs. https://www.cdc.gov/vaccines/vpd/mening/public/index.html
If your child doesn't have immune system issues, it's not critical, but if insurance covers the cost, why not get free protection?
A good friend of mine from college died from meningitis, before we were vaccinating for this. I'm not sure which type she had, but I say vaccinate.
Although it is rare, the disease can be serious if contracted. So the CDC recommends all children 11-12 years old to get the Meningococcal conjugate vaccine. Teens and young adults may also get a serogroup B Meningococcal vaccine. It can be given to other children. Make sure that you read the ingredients and that your child isn't allergic to any of the ingredients. you can ask your pharmacist or doctor about that. The side effects of the injection are possible flu like symptoms and soreness/swelling at the injection site. If your child has lowered immunity due to a disease, you would have to ask the doctor about whether it was right for your child.