I got a bit too cocky when I was in fourth grade, and it cost me dearly.

When the year started, I was on a hot streak for spelling tests. "Boulevard?" Basic. "Yesterday?" Child's play. It got to the point where -- even though we got the words in advance -- I didn't bother looking because I thought I had it made.

Then, "delicious" came along. I wasn't ready to navigate the slopes that this double black diamond presented, and it spanked me right in the grill. My hot streak was stopped, and I was forced to admit that I wasn't as smart as I had led myself to believe.

We thought we knew everything after Week 14 of the NFL season. Then Week 15 happened, and we're walking back to the drawing board with our tails between our legs. We don't have this puppy figured out just yet.

Because of this, we've got to make sure we put in the work and study our spelling lists by checking out usages across the league. We can do this using numberFire's new DFS tools, which are available for all premium members. These allow us to look at carry market shares, target market shares, and red zone market shares over the past one, three, and five games to see whose stock is rising and who's getting usage where it counts most.

Let's check what we thought we knew and take a look at each of these three categories to see the most relevant takeaways from Week 15.