It just seems like they are set up to fail, which makes them hate sport and sports day for the rest of their lives!
My DD is yet again in the sack race and skipping race.
A. She can't really skip so it will be a disaster.
B. The sack race is like some kind of medieval torture.
She was DESPERATE to be in the sprint or obstacle race, but apparently you have to rank top three in the practice to be in those races.
The sack race however is the 'didn't make the grade' race. It's a great idea isn't it? - let's take the least athletic, make them jump for 50m in a sack, with the almost 100% chance that they are going to end up face down in turf at some stage. That should motivate them. 
I feel so sorry for DD, as shes been in tears. I just feel like saying to the school to just let her run, if she comes last she comes last, but at least she won't be traumatised (again) from getting caught up in a skipping rope or going arse over tit in a sack!