I love to rise in a summer morn
When the birds sing on every tree
The distant huntsman winds his horn
And the sky-lark sings with me
O! what sweet company
But to go to school in a summer morn
O! it drives all joy away
Blake is attuned to the childish imagination, where birds and animals become ‘friends’. Sky-larks in particular are associated with joy and freedom. 

The Schoolboy