Corrected entry: Chrissy is the leader of Spirit Week and is trying to organise it. We see her kiss her boyfriend Troy, and suck the life out of him a few days before Spirit Week. However, Chloe pulls up the file on Troy, and it says his date of death is June 20, 2002. This is highly unlikely, as Spirit Week is put on in the days leading up to Homecoming, and Homecoming is usually in late September or October.
Corrected entry: Clark is supposed to hide his powers from everyone. When the other swimmer in the final race starts to drown Clark uses his super speed to get him off of the bottom of the pool. Everyone who was in the pool area had their eyes on the drowning kid so somebody should have seen Clark just appear at his side.
Correction: People would care more about him getting saved than who was saving him, so, no, they wouldn't have noticed Clark. He likely went slow enough as to not draw too much attention, yet of course still fast enough to save the one drowning.
The mistake is valid. Chrissy brings everyone's attention to Troy struggling in the water so people are stand at the edge of the pool looking into it before Clark reacts. Clark then uses his super speed to get to Troy on the bottom in an instant. People watching would have seen Clark move like a blur and then appear at Troy's side. When he brings him up, he moves at normal human speed.
Correction: Schools don't all follow the same schedules. While schools in nearby areas would have similar schedules, it's not unreasonable to think that one school's Homecoming is months away from another school's Homecoming that's on the other side of the country.
Knever