Dozens more children have been told to stay home after a seventh school was forced to close because of an infestation of spiders.
Newham Council has evacuated schools to treat the invasion of False Widow Spiders "immediately, before the eggs start hatching".
Hundreds of children in the east London borough stayed home while pest control experts scoured the schools.
False Widow Spiders are dark-coloured with globular bodies and range from 9.5 to 14 mm in size.
Although named because of its physical similarity to the killer black widow spider, the species' bites rarely cause death but can be very painful.
Symptoms include severe pain radiating from the bite and fever - but could prove fatal if a young and vulnerable child was bitten in an especially sensitive location.
Newham Council says it's supporting headteachers. Some schools could be closed until the end of the month.