Bullying has been researched extensively, and the findings about what works differ substantially from what schools and parents commonly do.
The definition
Research generally defines it as repeated aggressive behaviour involving a power imbalance.
Which distinguishes it from conflict between equals, and the distinction matters because the responses differ.
Conflict resolution and mediation approaches are appropriate for conflict and inappropriate for bullying, since they assume equal parties.
Forms
Physical, verbal, relational — exclusion, rumour, manipulation of friendships — and online.
Relational forms are the most common in most studies and the least visible to adults.
Online bullying frequently involves the same individuals as offline bullying rather than being separate, which several studies have found.
What works
Whole-school approaches have the best evidence, addressing school climate rather than individual incidents.
Meta-analyses find these reduce bullying and victimisation by meaningful proportions.
Elements associated with effectiveness include whole-school policy, staff training, classroom rules, playground supervision, parent involvement and consistent consequences.
Programme duration and intensity predict effectiveness, which means brief interventions do less.
What does not work
Zero tolerance policies, which have not shown effectiveness and are associated with reduced reporting.
Peer mediation for bullying specifically, for the power imbalance reason.
Group treatment of children who bully, which has shown iatrogenic effects in some studies.
And one-off assemblies or awareness days without sustained work.
Telling children to fight back or ignore it
Both are common advice and neither has evidence supporting it.
Ignoring rarely stops it and communicates to the child that adults will not act.
Fighting back risks escalation and disciplinary consequences for the victim.
Which means the advice most commonly given is not what the research supports.
Reporting
A substantial proportion of children do not tell adults, with reasons including fear of escalation, belief nothing will be done, and shame.
Which means the visible rate is lower than the actual rate, and that adult perception underestimates it.
Children are more likely to report where they have seen previous reports acted on effectively.
Consequences
Associations with mental health outcomes are substantial and can persist into adulthood in longitudinal studies.
Which applies to those who are bullied, those who bully, and particularly to those who do both.
The last group shows the poorest outcomes consistently.
What parents can do
Take reports seriously and respond calmly, since a distressed adult reaction can deter further disclosure.
Document specifics — dates, what happened, who was present.
Report to the school in writing, referencing their policy, and ask what will be done and when it will be reviewed.
Escalate through the school's complaints process if the response is inadequate.
And support the child's wider life, since friendships and activities outside the setting are protective.
Any indication that a child is at risk of self-harm requires immediate professional help, and support organisations for children and parents exist in most countries.
Online specifically
Continues outside school hours and can involve a wider audience, which are the features that distinguish it.
Evidence removal is a common instinct and is generally wrong — recording it first supports any report.
Platform reporting mechanisms exist with varying responsiveness, and schools have jurisdiction over online bullying between pupils in many systems.
Children who bully
Frequently have their own difficulties, and outcomes for them are also poorer.
Which means responses that address the behaviour and the underlying situation are more effective than punishment alone.
Exclusion has not been shown to reduce bullying.
Bystanders
Most bullying occurs with peers present, and their response affects whether it continues.
Which is why interventions increasingly target bystander behaviour, with evidence that it can be changed.
Peer support and defending are associated with reduced continuation.
Support
Anti-bullying organisations and helplines exist in most countries for both children and parents.
Schools' legal duties
Vary by jurisdiction and generally include duties to safeguard pupils and to have anti-bullying policies.
Which means a school failing to act may be failing a legal duty rather than only a moral one, and escalation routes exist including to governing bodies and regulators.
Where bullying relates to a protected characteristic, additional legal protections generally apply.
Changing schools
Sometimes the right decision and not a first response.
Which is because the underlying pattern can recur, and because it places the cost on the child who was harmed.
Where the school will not act effectively, it becomes reasonable.
Supporting the child
Maintaining friendships and activities outside the setting is protective.
Which gives a child a context where they are valued, and it matters more than any single intervention at the school.
Signs to notice
Reluctance to attend, unexplained injuries or missing possessions, changes in mood, sleep or appetite, and withdrawal from friends.
Which are non-specific and are worth exploring gently rather than interrogating.
Asking open questions about the day, regularly, makes disclosure more likely than asking directly whether they are being bullied.