Secured school bike rack lock requirements

TuckerUK
TuckerUK Posts: 369
Youngest will be started a new school in sept, and will be cycling there. The school bike racks are totally enclosed any can only be accessed in the morning, after school, or with special permission outside those times.

Obviously the bike still needs locking to one of the railings, but how secure does it need to be bearing in mind the above?

Any teachers and/or parents have experience of thefts from these types of bike racks?
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