Free for teachers
AI essay grader
Share a student's essay and your rubric. Sparky comments on the sentences that matter and drafts a score for each row of your rubric, for you to check before anything reaches the student.
Used by 250,000+ teachers, and built to FERPA, COPPA and GDPR standards.
How the essay grader works
Share the essay
Paste the essay into the chat, or attach it as a Word file, a PDF or a photo of the pages. You can also import it from Google Drive or OneDrive.
Add your rubric
Attach the rubric you already grade with. Without one, Sparky suggests criteria, like claim, evidence and organization, and waits for your go-ahead.
Check the draft
Sparky's scores and comments come back in the chat. Change what you disagree with in plain words, like "evidence is a 3, not a 2". To print or share the feedback, ask for it in a document.
What you get back
Comments on the sentences that matter
Sparky quotes the sentences it comments on, so you and the student can find them. Ask it to name what works as well as what to fix.
A score for each row of your rubric
Every criterion gets a score and the reason for it, drawn from the essay itself, so you can see why a row lost a point.
A note to the student
Ask for the feedback written to the student, ready to paste into your learning platform or onto the essay.
Criteria when you have no rubric
Sparky proposes criteria for the assignment, and you edit them before it scores.
Handwritten essays
Flint reads handwriting in photos and scans, so a paper essay doesn't need retyping.
More than one essay
Attach several essays in one message and grade them all against the same rubric.
AP Lang essays on the College Board rubric
The College Board scores AP English Language essays out of 6: thesis (0 to 1), evidence and commentary (0 to 4) and sophistication (0 to 1). Tell Sparky it's an AP Lang essay and paste the prompt, and it grades on those three rows.
A score for each AP row
Each row's score quotes the sentences that earned it. Sparky also says why the essay fell short of the next score, such as a 3 in evidence and commentary.
What would earn the next point
A note to the student on what to add. For an essay that names France's phone ban and moves on, Sparky asks what the ban showed.
Synthesis and rhetorical analysis too
The same three rows score all three AP Lang essays. For a synthesis essay, attach the sources too, so the evidence row can be checked against them.
Ways teachers use it
Argument essays
Score the claim, the evidence and the counterargument, with a comment on each paragraph.
Literary analysis
See where a quotation is explained and where it's dropped in with no analysis, and whether the thesis holds to the end.
Rough drafts
For comments with no score while students are still revising, use AI writing feedback. The essay grader is for the draft you score.
DBQs and lab reports
Grade writing in history and science against the criteria you set, such as sourcing or a conclusion backed by data.
Data privacy
Safe to use with student work
What happens to the files you upload and what your students write in Flint.
Not used to train AI
Student data in Flint is never used to train AI models.
Not shared
Flint does not share student data, or any other user data, with third parties.
Kept separate
Each school's data is kept apart from every other school's, and the AI providers Flint runs on can't reach it.
Signed agreements, on request
Flint signs a data processing agreement with any school that needs one, written to US state law and EU GDPR.
What teachers say about Flint
"By partnering with AI for aspects of grading, I can provide richer, more personalized feedback while maintaining consistent standards across all submissions, giving students the thorough attention and detailed guidance their work deserves."
Christa Forster
English Lit and Composition Teacher at The Kinkaid School
"Flint AI has become essential to my daily routine. I rely on it for differentiating instruction, writing comments, planning lessons, managing recess duty schedules, and developing rubrics."
Beonka Caldwell
4th Grade Teacher at The Kinkaid School
"From a professional standpoint, Flint's impact on teaching practice is profound. By automating tasks such as document formatting and rubric construction, Flint AI restores the teacher’s focus to pedagogy, discourse, and relational teaching."
Joseph Shannon
Upper School Literature and Philosophy Teacher at Chartwell School
Frequently asked questions
Is the essay grader free?
Yes. It's free for teachers, and there's no cap on how many essays you can grade.
Can it grade with my own rubric?
Yes. Attach your rubric or paste it into the chat, and Sparky scores the essay on each of its rows with your point values. If you don't have a rubric, Sparky suggests criteria and waits for you to agree before it scores anything. To write one first, use the rubric generator.
How accurate are the scores?
Treat them as a first read. Studies have found AI essay scores running both too high and too low, so compare a few essays with your own grades and change any score you disagree with. Our guide on whether teachers should use AI to grade covers the research.
Can it grade AP Lang essays?
Yes. Paste the prompt with the essay and ask for the College Board rubric. Sparky drafts a score out of 6, with the reason for each row, for you to check.
Can it read handwritten essays?
Yes. Attach a photo, a scan or a PDF of the pages, and Flint reads the handwriting. Check a few essays against the originals before you rely on it for a class set.
Can I grade a whole class at once?
You can attach several essays to one message and ask Sparky to grade each one against the same rubric. The length limit applies to each file on its own, not to the message.
Can Sparky comment inside a student's Google Doc?
No. Import the essay from Google Drive instead, then ask Sparky to put its feedback in a document. From there you can copy the comments into the student's doc, print the feedback, open it as a new Google Doc or download it as a Word file.
Explore more tools
See all tools ->
AI rubric generator
Make a rubric from your assignment or a one-line request, with criteria, levels and points you can edit, print or export.
AI writing feedback
Share a student's writing. Sparky drafts feedback that quotes the student's sentences, names what works and picks the next steps that will help most.
Report card comment generator
Give Sparky a few words about each student, or your gradebook export, and get a report card comment for each one.
