Parents who divorce have to tell their children about the major life change that's happening. This isn't always easy because of the raw emotions that come with the situation. Even though it might be difficult for you and your ex, it is best to tell the children together so that they can see you're still a parenting team.
If you have more than one child, you should tell them all together. Parents sometimes favor telling older children and waiting to tell the younger ones. This might seem like a good idea on the surface, but it can turn dangerous. The older child has to keep the split a secret, and the younger child might assume that you think they can't handle issues.
When you're thinking about when to tell the children, remember that it's best to tell them when they don't have anything else going on. Trying to tell them just before they go to school or when they're dealing with exams might not be ideal. Instead, pick a time when they can focus, and the talk won't be rushed.
Be prepared to answer some questions. Your children are likely going to have some strong emotions. You'll need to address those and offer comfort, but be careful not to give false hope. As you answer questions, be honest and keep things age-appropriate. Reassure them that this was an adult decision and that they aren't to blame.
It might be a good idea to have the parenting plan or a temporary agreement in place at this meeting. This lets you and your ex talk to the children about the new arrangement.