The biting water shortage in the city coupled with the ongoing rationing programme has hit public schools hard.
And it gets worse as many schools in the city have had the little water they had disconnected for failing to pay their water bills.
The hardest hit are public primary schools that fell under the defunct Nairobi City Council, now Nairobi City County.
In Madaraka Primary School, taps have been dry since the Nairobi Water and Sewerage Company (NWSC) disconnected them three months ago.
The school owes the company Sh105,000, which must be settled completely before re-connection.
"Water has been a problem and we cannot charge parents anything additional to cater for the bills. What the Government has allocated caters only for electricity, which we've been paying," said head teacher Rose Githinji.
Ms Githinji said sanitation was a big problem in the school because of the lack of water.
"We fear there could be an outbreak of waterborne diseases," she said.
The situation was the same at Langata West Primary School despite the fact that their water was reconnected last week.
The head teacher, Philomena Sungu, said the school received water only once a week and sometimes there was no water at all. The school is unable to sustain the sanitation requirements for the over 1,500 pupils.
"The biggest problem is that even when water finally comes, mostly for one day in a week, it is not enough; not even with our little storage capacity," she said.
With devolution, schools were required to pay their own water and electricity bills unlike in the past, when water was provided by NWSC on arrangement with the Nairobi City Council.
Some of these schools also lack the capacity to harvest rainwater due to poor storage capacity.
Many of them have been forced to seek alternative ways to foot their bills.
The Fourth Schedule of the Constitution vests the responsibility of providing schools with water on the national government, alongside free education services
Mbaruku Viakweli, the NCWSC head of corporate affairs, said the company supplied water to schools and they were all expected to pay.
He said the company had reconnected water for 14 out of the 17 schools that had been disconnected since they had paid.