To give the student daily dairy, follow the below path:
Communication --> Diary --> Student Diary --> Select the classes and Date "Get" -->click on +Diary-->select Type of diary,class-section,subject,Date-->Give the diary, if want to add or upload any attachments click on choose file under the attachments-->click on save.
Note:
The subject teacher can able to post the diary based on the assigned subject. However, the Class teacher/Class Co-Ordinator/Principal can able to post the diary for all the subjects.