planning lessons for a specific purpose, such as teaching some coding paradigm or skill. Planning lessons in Computer Science depends on the context and level of the students. If it is a lesson which introduces a new topic, the tag [introductory-lesson] may also be appropriate.
Problem solved. I just changed the tags on the three questions so now lesson-planning has none. It had no tag wiki in any case.
Note that whenever I find a brand new tag that has no wiki, I try to see if we already have one (or two) that covers the case and is already used. In that situation I consider replacing the new tag with older, established, ones. The proliferation of tags can actually make it harder to find related things.