If user doesn’t understand the idea of categories, and in our site, there’s one category (called “teaching and learning”) that will contain the vast majority of posts, then how do I make “teaching and learning” appear in the category drop down initially? Thanks!

You can not easily control the order there, best you can do is disable uncategorized from site settings

Thanks. Are they alphabetized in UI. I could artificially name my default category to something that sorts first?

Or, I could rename “uncategorized” ?

The ordering of categories is a long and contentious topic, see: https://meta.discourse.org/t/category-ordering-broken-in-places/17025 for some more context. We display categories in a list in 4 spots but not all of them will respect fixed category positions

[תמונה] pitosalas: that will contain the vast majority of posts, then how do I make “teaching and learning” appear in the category drop down initially? If it does contain the majority of posts, that will happen automatically.

Is there an option to rename the category “uncategorized”?

Yes, you can rename the uncategorized category. https://bbs.boingboing.net/ did that.

Setting up a 'default' category

Support

נושא		תגובות	צפיות
Default category Feature	33	7563	20 במאי,‏ 2019
Renamed our "uncategorized" Category at setup....backed myself into a corner? Support	10	1193	30 באפריל,‏ 2018
Should the order of categories in every place being the same? Feature	5	1108	29 באוקטובר,‏ 2014
How to set default Topic 'Category' Support	6	626	3 בספטמבר,‏ 2020
Change sort order for category choice in new post Support	2	842	15 בפברואר,‏ 2021

Setting up a 'default' category

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