Singing Time Olympics

I'm preparing now for the next two and a half months worth of singing times. Yes, it's crunch time...also known as the months leading up to the Primary Sacrament Meeting presentation. (They changed the name from "program" to "presentation." What's the difference?)
Last year the lady who was in charge in our ward worried that the kids didn't know the songs well enough, so she split them into smaller groups and had mini-choirs. I really DID NOT like it that way, so I promised myself that THIS year I'd drill those songs into the kids' heads so much that they'd be singing the songs in their sleep.
I have always enjoyed this special meeting in church for as long as I can remember. And my MOST favorite part was hearing the entire primary sing the songs together. So last year when she split the kids in to small groups for singing the songs I was highly disappointed. I didn't feel like it was the same thing.
ANYWAY...We've reviewed and reviewed the songs. And as usual there are some songs they know so well they are tired of singing them, and there are others that they mumble their way through because they DON'T know the song like they should.
As I've mentioned before I'm planning on doing a Singing Time Olympics, and now I'm getting ready to start it. I printed off the words I'm going to use for my point-keeping posterboard, and made them pretty. I've had my score cards printed off for a while, and now to implement the plan.
The plan is to have the primary presidency judge the kids (I may have guest judges come in every once in a while, but I'm not sure yet.) They'll judge the kids tomorrow according to how well they know the words. I'll have them judge the kids' knowledge of the melodies next week, and the volume on the next week. After judging in the three different areas, I'll have them judged in all three areas with an overall score. Each week I'm going to keep track of the scores that both Junior and Senior primaries have, then I'll transfer the scores to my posterboard...keeping it posted for the whole time we're reviewing. Which ever section wins the "contest" will win gold medals, but the other group will win silver medals...I just won't tell them that they'll BOTH get prizes...I want to maintain a competitive spirit.
For the first little while I'm going to have the songs picked come from my autumn tree. The kids will pull yellow and orange leaves off my tree and sing the song that's on the back side. I have a plan for the end of the month to do name that tune. I'm still trying to come up with fun ways to pick the review songs. I also have an ark set up where there are songs on the back of the animals and people that you put on the ark...I may have to update that and use it as well.
I had a dream about my new plan last night. It was weird (as most of my dreams are...) and in it I couldn't find ANY of the stuff I had planned. I was so upset, but managed to improvise. But, in my dream I had a poster with a sun on it...I guess they put the rays of sunshine on it, wanting to make the sun shine bright. I may actually use that idea, but I may not.
If you have any other great ideas for review games...please share them here. I'm hitting a mental block, and I hope I can get over it quickly! I'm really excited for this new singing time Olympics thing though...it should help me keep the kids' interests while we're just singing the same songs over and over and over.