I’m not from this country and come from a country where recycling is highly embedded in society, supported by well developed process that sure to limit non compliance.
Households pay for the rubbish bags issued by the council. They are marked for general usage, recyclable plastics, organic, food waste, paper and cardboard. The most expensive bags are the generic waste ones, followed by recyclable plastics, etc.
Items need to be cleaned before they’re put in the bags. The bags are picked up at different times according to the type of rubbish. If a non-compliant bag/item is deposited, the whole bag is not picked up. If someone gets caught depositing illegal rubbish, they get fined.
I understand the UK needs to invest more in infrastructure to have enough capacity to manage waste, to prevent the export of plastic to other countries.
https://www.bpf.co.uk/press/exporting-plastic-waste-for-recycling.aspx
I am not sure what steps the current government or the next will take to tackle this problem. From your comments and the Google search I did, it looks like the data from schools may be partially used to assess the amount of rubbish. I didn’t see that practice in my country, hence the suspicion.
I hope this comment was beneficial to those who commented, and those who read it.