Question: What is a syllabus? Is it different from シラバス?
(See the comments under the Japanese sentence.)

I've never heard that katakana before so don't know. 授業計画 is another possibility.

A syllabus is a term or year's instruction plan all on one or two pages. A lesson plan, in contrast, is typically a page or two for one single class (hour).

They (シラバス and syllabus) mean the same, don't they?

Here's one example I found online.

http://cals.ufl.edu/students/do...Spring2014.pdf

This looks similar to the シラバス I submit to my university.

What is "they"?

シラバス and syllabus

is a syllabus a [fra]plan de cours ?

To me, a syllabus is a manual of a given topic (history, mechanics...)

In English, "syllabus" means something like "lesson plan". For example, a teacher might create a syllabus for that year's class. I have never heard the word used to describe manuals.

Just checking, because the Japanese sentence was initially mistranslated in French and I was misguided by Dutch, which uses "syllabus" as meaning "manual", which is indeed etymologically wrong.