I can only speak for myself but I am also a teacher and eventually my body adapted to only eating after work. I felt a bit of hunger for the first few days but eventually felt fine. You could do it for a few days in a row and see how you feel, or just have a light meal or snack in the early afternoon if it is that bad. Also - coffee helps!
The main reason I switched to omad actually is because I felt sluggish after eating. Dealing with 12-15 year olds with a belly full of food was very difficult. I actually find that now I have more energy, though sometimes it’s a bit of a frenetic energy.