Explica

Explica takes a deliberately different stance from general-purpose chatbots in the classroom. Where a chatbot will happily hand a student a finished translation or a completed essay, Explica is built to explain rather than to substitute. It works entirely inside the browser: install the extension once, then highlight any word or sentence on any page you already read, from news articles to assigned PDFs, and get an explanation written in the target language and calibrated to the student's level.

For teachers, the extension doubles as a lightweight classroom console. Teachers can set a minimum explanation level per class so students can't quietly drop down to full English translation, assign PDF readings with tracked active time and per-page lookups, and see engagement signals such as lookups per student and the vocabulary the class searched most. Writing assignments are drafted inside Explica, so large pastes are recorded and shown to the teacher as signals to ask about — never as accusations.

Pricing spans individual learners, independent tutors and whole institutions. Individuals pay a modest monthly or annual fee, tutors get a teacher dashboard with a few student accounts included, and schools can license an email domain so every student and teacher is recognised automatically at sign-in. All plans include the full set of roughly 20 supported languages. Currently a Google Docs add-on is in development, since Docs renders text on a canvas that browser extensions cannot read.