These children won't be there long. It's a publicity stunt, I'm betting.
Still, they're outside the fence of this facility. Intelligent armaments will strike the actual facility, where they will do the required damage. Collateral damage probably won't extend far enough to endanger the children.
We're pretty good these days at destroying facilities with little collateral damage. We've all see the results of our current armaments.
I have no doubt that Israel is equipped with equally good materiel. It will be an interesting exercize for the Israelis to disable this facility. I expect that they'll be acting shortly.
Perhaps they're waiting for all the goodies to arrive at the facility, so they can destroy as much as possible. The kids will be gone, no doubt, once the cameras are gone.