Investigating suspected plagiarism

One of our students just submitted a project (TEALS Intro to CS Unit 6) that the teacher (I'm one of the TAs) suspects has been plagiarized. Any ideas how to search for a comparable program on the Web? I checked here:, but didn't see any immediately obvious similarities, and I won't do a manual search of 3,662 published projects.



P.S. Here's my copy of the project:

Why does the teacher believe it is plagiarized? Can the student no explain the code, or is it similar to another student's work?

Too advanced. (It is not similar to any other submitted work this semester.) It's as though a student who had been struggling with long division suddenly turned in a breakthrough scientific paper on quantum gravity. (I'm exaggerating, but you get the idea.) There is a body of work for each student, stretching over an entire semester, and this student hasn't written anything anywhere near as advanced before.

The teacher hasn't had time to have the student explain the code to her.

If one could get a database of all published project's XML files, it might be possible to use a system compares your project to every other one.

You may custom search. @bh or @jens may know about it.

How? Where? I would need to search inside the program for a match. If it was taken from a prior work, the name has been changed.

I can't understand what are you saying.

You said: "You may custom search." I am asking you how to do that. I have no idea.

Well, you may use Google Custom Search.

Talk to the student and see if they can explain it, the code still seems pretty basic and it could be that they have just been playing around with Snap!

That might be a good idea, but he or she, i.e. they may lie.

Is the project a game?

Found it. He got it from Scratch, and then ported it to Snap!


Did he make it by his own on Scratch?

No, he did not.

Okay. That's bad though. Have a great day! Merry Christmas!

To add some context, and answer this for any related questions:

We do not have an easy way to search the contents of projects, only names and descriptions. Naturally, it's possible, but requires a significant amount of effort we cannot support.

The search box only searches published stuff, and there's still relatively few published projects. Projects that are "shared" (meaning via a link only) will not show via searching.
It's not terribly hard to translate a Scratch project into Snap!, and so far this has been the vast majority of copying we've seen or had reported to us.

I had a student turn in the TEALS Intro CS Project "Pong" a couple of days after it was assigned. NO WAY--not this student. I didn't know it yet, but they had gone to Snap! > "Snap! website", and found someone's Pong project. They clicked "See Code", and then "Save as...". Now it appeared to be their own project, and they turned it in.

HOWEVER! I opened their project, did (Cloud menu) > Open in Community Site , and there it said: "by (remixed from by )". CAUGHT! I went back, and it turned out the student had plagiarized (verbatim) all the Labs for the last 5 weeks. The student denied it, of course, until I dropped two stacks of code scripts, theirs and the originals.

This only works if "Open in Community Site" shows up under the (Cloud) menu. Unfortunately, if the student does "Download" and then imports the XML file, the remixID is lost.

I don't think we can ever give you an ironclad guarantee that a student submission isn't plagiarized. But I'm hoping that over the course of this academic year we'll be developing student accounts, distinct from regular accounts, which won't be allowed to publish projects or comments.

But we'll encourage students also to have a regular personal account, so if they really want to, they can manage to publish their homework. We really don't like telling people they can't do things, but we don't mind making it hard to do bad things by accident.

When I started teaching at Berkeley, back in 1987, when students were caught cheating and called into my office, they burst into tears and confessed. By the time I retired in 2013, they'd look me right in the eye and calmly deny it. This was one of the reasons I retired early.

I don't blame the students; I blame the hyper-competitiveness of society and also the shift toward money manipulators as the heros of the culture in the '80s.

Hi Brian - I'm wondering what the student accounts will be like? I ask because I co-teach with another teacher and a lot of platforms don't allow multiple teachers to access student content. This is a big concern of ours as we support students with disabilities we would very much like to both have access individually rather than create a shared "teacher" account that we both have to share. If the students don't publish it - how do teachers view it?