Steve let out his breath. "Doc," he said, keeping his voice soft. "Something's going on. You probably won't believe me, but the timeline has gotten--"
He happened to glance up at the window as he was speaking, and saw the shape across the street. His words turned off, and Steve really, really wished he had his shield. But he didn't. It was back in the TARDIS. So instead, he picked up a large, circular platter from the table, curled his arm back, and let the dish fly, calling out, "Everyone, get under the table!"
The platter didn't have the same aerodynamics as his shield, but Cap's aim was true, and the dish sailed out the window, straight into the figure standing across the street. Steve didn't hesitate, following an instant later to put himself between the window and the children.