The design of levels for computer games is a form of programming, particularly for games with deterministic NPCs. It seems to me that for a large portion of the modern computer user-base the design of games levels will be their first experience of programming computers, the people who don’t start programming by creating games levels would be writing spread-sheets. Probably a few people start programming by writing “batch files” and shell scripts, but I expect that they form a minute portion of the user-base.
I believe that learning some type of programming is becoming increasingly important, not just for it’s own sake (most people can get through their life quite well without doing any form of programming) but because of the sense of empowerment it gives. A computer is not a mysterious magic box that sometimes does things you want and sometimes doesn’t! It’s a complex machine that you can control. Knowing that you can control it gives you more options even if you don’t want to program it yourself, little things like knowing that you have an option of using a different choice of software or paying someone to write new software open significant possibilities to computer use in business environments.
Games which involve strategic or tactical thought seem to have some educational benefit (which may or may not outweigh the negative aspects of games). To empower children and take full advantage of the educational possibilities I think that there are some features that are needed in games.
Firstly levels that are created by the user need to be first class objects in the game. Having a game menu provide the option of playing predefined levels or user-defined levels clearly shows to the user that their work is somehow less important than that of the game designer. While the game designer’s work will tend to be of a higher quality (by objective measures), by the subjective opinion of the user their own work is usually the most important thing. So when starting a game the user should be given a choice of levels (and/or campaigns) to play with their levels being listed beside the levels of the game creator. Having the users levels displayed at the top of the list (before the levels from the game designer) is also a good thing. Games that support campaigns should allow the user to create their own campaigns.
The KDE game kgoldrunner  is the best example I’ve seen of this being implemented correctly (there may be better examples but I don’t recall seeing them).
In kgoldrunner when you start a game the game(s) that you created are at the bottom of the list. While I believe that it would be better to have my own games at the top of the list, having them in the same list is adequate.
When a user is playing the game they should be able to jump immediately from playing a level to editing it. For example in kgoldrunner you can use the Edit Any Level menu option at any time while playing and it will default to allowing you to edit the level you are playing (and give you a hint that you have to save it to your own level). This is a tremendous encouragement for editing levels, any time you play a level and find it too hard, too easy, or not aesthetically pleasing you can change it with a single menu selection!
When editing a level every option should have a description. There should be no guessing as to what an item does – it should not be assumed that the user has played the game enough to fully understand how each primary object works. Kgoldrunner provides hover text to describe the building blocks.
Operations that seem likely to be performed reasonably often should have menu options. While it is possible to move a level by loading it and saving it, having a Move Level menu option (as kgoldrunner does) is a really good feature. Kgoldrunner’s Edit Next Level menu option is also a good feature.
Finally a game should support sharing levels with friends. While kgoldrunner is great it falls down badly in this area. While it’s OK for a game to use multiple files for a campaign underneath the directory it uses for all it’s configuration, but it should be able to export a campaign to a single file for sharing. Being able to hook in to a MUA to enable sending a campaign as a file attached to an email as a single operation would also be a good feature. I have filed Debian bug #502372  requesting this feature.