Well I didn't mean stick with one thing, more pick a subject each week/month and capture it with a different lens each day/week type of thing - exploring the characteristics of each lens as much as expanding or refining your interpretation of whatever you're shooting.
Obviously it also needs interesting enough subject matter to not get bored doing that.
That's what I meant. Go out with a single lens each time and have certain subject types/situations in mind. Especially if its fixed focal length so you have to be more creative and imaginative.
I just got the cheapo canon ef-s 10-18mm lens. Not had a chance to use in anger yet, as it's arrival signalled the end of the dry weather with nice sunsets :(