Under health and safety law, you need to assess any risks that may arise during school activities, take steps to prevent hazards, and record the findings of your assessments (as explained in DfE advice on health and safety in schools).
There are certain risk assessments you must have in place, but also other areas where you'll need to assess risks, depending on your facilities and activities.
A playground/breaktime risk assessment can help you meet your health and safety responsibilities and reduce risk for your pupils.
Risk assessments: see what other schools do
Take a look at these examples if you're not sure what to include in your own:
Download a risk assessment template if you don't already have one, or need to carry out a