Their aim is to create the perfect jam sandwich by hitting (with their stomach and bodies) the 'filling' at exactly the same time. This results in anger, some pain and often a bewildered wilting to the schoolyard floor by the squished 'jam' and occasionally the 'slices of bread'.
Of course the jam player can, if they are quick witted and agile enough, realise what is about to happen and dive out of the way at the very last moment, resulting in the breads smashing headfirst into one another and being toasted.
If you play odd games then contact me: montegue_blister@hotmail.co.uk and tell me all about it...if you want