Bouncy balls are the starting point here, but the poem is really about a happy moment on a playground or street. It opens with "small spheres" in the sun, a plain, almost scientific way of naming the balls, and then quickly moves to what matters more: the children playing with them.
The speaker seems to be watching from the side, simply enjoying the scene. Nothing dramatic happens. Instead, we get a few bright details: shadows stretched across the concrete, laughter in the air, friends looking out for each other. The repeated lines about shadows and children having fun work like a chorus, or like the bounce of a ball coming back again and again.
The mood is light, warm, and carefree. The short lines and simple rhymes ("fun," "care") feel playful, almost like a nursery rhyme. The poem suggests that happiness can be small and ordinary, found in sunshine, a ball, and good company.