First, don't just abandon this... It's a cute sort of throwback idea. It's worth exploring a little more. I just honestly think it needs a little work.
Minimal, you'd be really well advised to go back through and change the color of your fonts. Dark colors for bright backgrounds, bright colors for dark backgrounds... Sticking to plain white loses words in a couple places. Okay, to me (chronic reader) it's only somewhat annoying since I am fluent (enough) in English. However, YouTube allows you to broadcast to an international level of fanbase. If you don't bother with making sure the text is visible and readable, you're only cutting yourself short of possible fans (even just a few who'd watch to get some English practice on a silly, short song...
Most bang for least investment improvement?
Go back and watch Shirley Temple and listen. Replay and sing along to match her keys. Yes, you can manage it without a voice coach... aside from the fact you'll get sick of "Animal Crackers..." but you will be able to hear when your voice matches keys with hers. Then you'll be better able to get this to sound right. It's a lot of practice, but we're talking audio effect... And good audio will save even the worst visual work (and yours isn't bad)... Bad audio can (and usually will) sink the greatest visual effects and work ever. Thus I submit to you, if you're going to parody a song, you should probably parody it well. You did good through the first line, real close... We're not talking perfection here, so a fair amount of effort on getting the rest of the tune together (and hey, you might think of some further lyrics for your own along the way) and you'll have a much improved product.
While not exactly my favorite style (okay, what is? Right?) the animation was good quality. It was also consistent. You're not trying to be Pixar, but you've shown some degree of actual skill and the attention span to apply it. The quality of audio was also good... clear words, understandable, and reasonably well managed. You weren't obnoxious nor did you assault ears with something unpleasant or try to overdrive volume controls. Just tuning your voice, or even getting a played score of the original to sing with could help sing it instead of say it. It was never a rap...
Overall, good idea, good work... I just think it can be so much better without a whole lot of extra put into it. Hope you either do it, or take the notes from here for the next project (with a plan to revisit this in the future)... Now, don't forget to breathe, relax, and keep on keeping on...