Data modeling a timesheet

I have an existing application that lets a company track the tutor/ student relationships through a Job model. I now want to add in functionality that lets the tutors login and enter the time they spend each week tutoring for each of their respective jobs.

im building this functionality into a rails app, but im not sure if im modeling it in the best way.

For each active job there is a row that lists the client's name as well as each day of the week (monday -> Sunday) so the tutor can enter their hours, and minutes for that day.

I'm going to create a Timesheet model that stores the tutor_id, year and week # (so I can just calculate the first day of week and iterate from there). The Timesheet model will have a has_many relationship to an Activity model that has the timesheet_id and job_id.

Activity will then have a has_many relationship to a Day model that will include the date, hour and minute fields for each day.

Im not sure if that is the right way to go about it though.

class Job   belongs_to :student, :tutor   has_many :timesheets end

class Timesheet   belongs_to :job   has_many :days end

class Day   belongs_to :timesheet end

Here's a screenshot of my mockup for reference:

Any suggestions are appreciated.