I'm surprised that her kindergarten doesn't have a morning snack-- a lot of kids eat early around 6:30am and they get hungry way before lunch-- esp. little kids... maybe ask her teacher if they can eat a snack during morning playground? that's what my daughter's school does.... i would NOT like to teach a class of hungry five year olds :)
anyway-- my girls eat "breakfast"" in the car-- bad, I know, but they are not hungry right when they get up, and i want them to eat a little something. basically, they drink a glass of milk (in a covered cup, or sippy type cup to head off spills) and they munch on cereal in a baggie, or a banana or grapes, or a slice of bread w peanut butter or nutella folded over, a healthy but yummy mini muffin, a cereal bar, a hard boiled egg, a cheese stick and multigrain crackers, a yogurt stick or drink, applesauce, etc. try to think of something fun and appealing and healthy-ish that she would like to eat. As pp said, it doesn't have to be a traditional breakfast type food.
the good thing is they are little so they don't need a huge breakfast, esp if she can eat a quick morning snack at school...
and she might be one of those people who doesn't need much in the morning,,,,
good luck :)