Yeah, I hate those threads 'I need help, urgent!' and the guy needs a project, any project. This forum is full of project ideas, schematics, and circuit descriptions.
Unfortunately, there is no practical way to filter out lazy students, as there are a lot of children wanting to get started in electronics. It's not an easy thing for them, when their parents aren't even sure which end of a soldering pencil to pick up (even after getting burned). Then there are the different languages. English isn't that easy, and learning electronics... got to be a tough one, then some SOB throw's a PIC at them too.
Personally, I'd prefer to know straight off that its a school project, rather than get scammed into helping. I don't think helping out is such a bad thing, just not doing the whole thing. I'm sure everyone had understanding one or two things in school, and need to hear it from several people before it started to make sense.
Even if the students are handed a schematic, the still need to build it, troubleshoot it, and present it to the class. Sure, they take some short cuts, but they'll learn something in the process.