I've got valspar paint which in theory is washable but magic erasers aren't up to the job. DD has marked her walls so heavily I can't get any of the pencil and pen off her walls, or ceiling 
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Has anyone tried grafitti remover for this sort of thing? Or will it just take the paint off to the plaster 
, I'd do a test patch first obviously. DD is likely to draw on the walls again so I'm not keen on repainting at this stage. But it would be nice to freshen her room up again.