I have a large group (20) of high school soccer players that want to come there for breakfast. Do you take/need reservations or should they just show up?

In the summer its easier for a large group, they have the outside patio!

Call and give them a heads up, that's a lot to spring on them.

Yes call ahead. They are a wonderful group of people

I would call ahead just so they can accommodate seating. They are an awesome group, I'm sure they'll take care of you!