There isn’t a way to attach a note to specific day on an assignment, but you can use the Daily Note feature to add a note to today.
Are you using a resource with no divisions for the poetry? If you make a resource with a division for each poem you plan to cover (you don’t have to name them), you can mark each division completed and add a note with the poem title. That note would then be tied to the date you read the poem. We have a video about doing this called Special Resources that might be helpful.
