If you make a petition with the official website and it passes they have to deal with it, even if its a rejection.
Dependent on the project, other categories might work too. The list is in Abgabenordnung §52 ( https://www.gesetze-im-internet.de/ao_1977/__52.html ) / Fiscal Code Section 52 Public benefit purposes ( https://www.gesetze-im-internet.de/englisch_ao/englisch_ao.p... )
(Contrary to intuition, "advancement of science and research" is very hard to get accepted in unless you're a university or at least publish papers in journals. And while the law claims that in theory other purposes could be argued for, in practice tax authorities will simply stick to the list and not make exceptions.)