The speaker is walking in the woods when distant shrieks drift over, and at first they sound like coyotes. Then comes the correction: they're children, probably at play. The title, "Primary school," suggests a class outing, though the poem never says so outright. That small mistake sets the tone, since the children's joy sounds wild and a little dangerous from far away.
The speaker then asks, almost to themselves, "When did I stop climbing trees?" It reads as a quiet pang of loss, a sense that caution has crept in without being noticed. The line about views being "seasoned with a little terror" answers the question: risk makes the experience richer, and the speaker misses that.
The last image, a dead cicada stuck halfway out of its old shell, is stranger and more open. It might suggest being caught between stages of life, unable to fully leave childhood behind or fully move on. The mood is wistful, curious, and slightly uneasy.