I can always tell who is wearing contacts in the Knife Skills class -- the people who don't cry even though we are cutting 18 onions. There are 9 of us (8 students plus an instructor) and we each get one onion to slice and one to dice. If you do the math, that's a lot of tears. I really wish I had some good solution to the crying problem. Sharp knife helps a lot, so is good technique. If you learn to do it correctly, you can eventually do it quickly. But when there are 18 onions involved, it's tough unless you are wearing contacts, or swimming goggles, or have at some point in your life worked in a restaurant (a daily dose of 25Lb of onions builds immunity in just a few weeks).
Here is what always bothered me about this part of the class. By the time it's students turn to dice the onions, some of them are so teary and disoriented that it's hard for them to see the board, let alone remember all the steps of this somewhat complicated technique.
But thanks to YouTube, Flip Camera, and Janet's help, I now have a video of how to dice an onion. If you were too teary to remember all the steps from class, you can always watch this as a reminder.