[With poetry it is better to paraphrase by sentence or grammatical unit, rather than by line.]
The shades in the classroom are drawn so that the boys are working in the colorless shade.
Occasionally, the wind blows the shades, creating colorful slants of light across the walls.
I feel like their source of strength as I watch the boys work. Every now and then one will look at me and then go back to work.
Sometimes, when they raise their heads, I can tell that they finally understood something and are proud of themselves for it.
This is the best part of the day, the part when I can tell that the light is finally coming to them. I am making a difference!
They are like little birds; the understanding seems to make them work that much harder and fly that much higher.
Each time they understand something new, the fly a little higher. It is kind of like creating a new tree with them growing and sprouting new leaves while I form the solid trunk and foundation.