Vocator
Vocator is an online vocabulary learning program that I developed when I was in 10/11th grade.
During my school life I tried different programs for doing my English and Latin vocabulary training. The program I used the most is called Teachmaster and I would still recommend it to anyone who is looking for free, offline vocab learning software.
The main issue I had with these kinds of software was that I always had to enter all the words by myself. Besides taking a lot of time - if you make any errors during that process you might actually start learning misspelled words.
I thought that me and my classmates would become much more avid learners if we could simply go to a website and learn their vocabulary, without having to set up anything or enter the words manually.
There is already software out there which has this feature (like Phase6), but it is quite expensive (about 40€/year).
So I thought about making a vocab learning platform for schools. There would be a central vocabulary storage for the entire school, to which every teacher could contribute his units.
The teachers can set up classes, add one or multiple units to them and give their students a code so they can join them.
The students have an overview of all of their classes and units. Once they click on the "Learn" button, the program shows them random words and they have to enter them in the respective language. Every word guessed correctly grants the student one point. The vocabulary table of each unit can even be exported to a pdf file, if one wants to learn their vocabulary the classic way.
There is also a ranking of the students with the most points to encourage competition.
However the development of vocator pretty much came to a stop when I was in graduation class, because then my class pretty much didn't need to do any vocabulary training any more. And without participation and feedback from my classmates I didn't see much sense in continuing the development.
Looking back at this, there is now a bunch of stuff that I would do differently if I had to develop the same project with the knowledge I have today. Especially on the frontend side there is a lot of duplicate javascript code. But also the backend could be much more streamlined if I had used classes, PHP imports and did not put HTML and PHP in the same files.
I also did not know about SQL injections and how to avoid them back then, so Vocator is probably vulnerable to them (although I haven't tried to hack my own website).
There are also a bunch of features left to be desired, for example virtual card boxes or some other way of tracking how well you know a single word.