Gaza's civil defence agency said Israeli bombardment of two schools in Gaza City killed at least 25 people on Sunday.
"The bodies of 25 martyrs, mostly children and women, and 50 other wounded, also mostly children and women, were taken to Baptist hospital after an Israeli strike targeted Hassan Salameh and Al-Nasr schools in Gaza City," agency spokesman Mahmud Bassal told news agency AFP.
The strike followed a similar bombardment of the Al-Hamama School in Gaza which killed 17 displaced people
Earlier on Sunday an Israeli airstrike killed four people, including one woman, in a tent camp housing displaced people inside the courtyard of the Al-Aqsa Martyrs Hospital in central Gaza.
In Israel, a 66-year-old woman and an 80-year-old man were killed in a stabbing attack in Holon near Tel Aviv, according to Israel's Magen David Adom rescue service, and two other men were wounded.
The Gaza war is now in its tenth month and over 39,000 people have been killed as a result of indiscriminate Israeli bombardment and ground attacks on the territory.
Fears of a wider regional war have increased recently amid the killing of Hamas leader Ismail Haniyeh in Iran and senior Hezbollah commander Fuad Shukr in Beirut last week, with Iran vowing retaliation against Israel for Haniyeh's killing.