It's a great idea. The most important part (possibly the only important part) of learning to code is to actually write code, code that's useful to you. Small commits are a good habit (too many people have an SVN-era instinct that commits are "expensive"). Heck, if I were doing this (as someone with a full-time job that's mostly coding) I'd make it a branch every day, with at least 8 commits on it. (Perhaps if you want to follow CBHacking's suggestion you could make it a branch every week, with at least 7 commits on it; that way, to be "on target" you commit every day, but you can miss a few days and make it up if you need to).

My standard way to avoid the "what the hell effect" is: miss one and it's ok, miss two and it's all over.