"Schools are supposed to be safe places for children, protected under global law, yet they are being attacked every single day", said Sonia Khush, Save the Children's Syria Response Director in a statement.
The United States says Syrian President Bashar Assad's use of chemical weapons and bombings against civilians "must stop now".
"We join you in opposing the Turkish government's military assault against the Kurdish people in Syria and we condemn Washington and Moscow for giving a green light to this aggression", Patrick Brown told demonstrators, speaking for the Communist League.
American advisers have been based with their Kurdish and Arab counterparts since the fall of Islamic State in the country late past year.
"Russia must use its influence with Damascus to ensure the Syrian regime immediately allows the United Nations to provide vital assistance to this extremely vulnerable population".
Diplomats said it was unclear whether Russian Federation would use its veto to block the new draft resolution. "We might lose a helicopter, but they'll pay the price for this".
In Eastern Ghouta, the surge in attacks has coincided with the sharp rise in violence in Idlib.
Elsewhere in the war-ravaged country, fighting continues to take its toll with a number of civilians, including children, reportedly killed and injured in Afrin district in north-western Syria.
The military's statement said the soldier died in clashes with the Syrian Kurdish group known as the People's Protection Units, or YPG. "Eastern Ghouta is experiencing a Middle Ages-style siege".
Ford was the last USA ambassador to Syria and now teaches at Yale University and is a fellow at the Middle East Institute.
YPG is the main fighting force of the US -backed Syrian Democratic Forces (SDF), which played a key role in the ongoing fight against the Islamic State terror group in the region.
The Syrian government has repeatedly said it only targets militants. It said the dead includes a medic and at least 10 children.
Western powers have expressed alarm over the government's campaign against Eastern Ghouta, where 400,000 people have been besieged since 2013, facing severe food and medicine shortages. At least 169 civilians have been killed since Monday. However, the US made a decision to step back, saying that they no longer held an interest in Afrin.
But the USA denies those connections and sees the YPG as a key ally in the battle against the Islamic State.
The doctor in Eastern Ghouta listed the casualties of a bloody day. Calling for "urgent worldwide action" to protect civilians, Zeid also slammed what he called an "epic failure of global diplomacy" to end the seven-year-old war.
Rescue teams rushed to Jisreen and pulled three children and a woman out of the rubble.
The U.N. Security Council is expected to hear a briefing on Thursday and then hold closed-door consultations on the growing humanitarian crisis in Syria and calls for a 30-day cease fire.
Turkey's military announced the death of another soldier in its operation against a syrian Kurdish militia in northern Syria, on Sunday.
According to the Turkish General Staff, the operation aims to establish security and stability along Turkey's borders and the region as well as to protect Syrians from terrorist oppression and cruelty. The latter is designated as a terrorist group by Turkey.
SANA labeled it an "aggression" and a "new massacre". The state Al-Ikhbariyah TV said there were reports that dozens were killed.
The Iranian president further underlined the need for boosting trilateral ties among Iran, Turkey and Russian Federation and welcomed an upcoming meeting in Istanbul between the three countries' presidents on the Syria crisis.
Turkish President Recep Tayyip Erdogan says one of the country's military helicopters has been shot down near the border with Syria.
Meanwhile, Turkish officials said the leaders of Turkey, Russia and Iran will meet in Istanbul to discuss peace efforts for Syria.