What happens when an elementary field trip walks into a trauma situation? Tonight’s Grey’s Anatomy season 11, episode 18, plans to show you.

If you run a school in the Seattle area, and read any reports that come out of Grey Sloan Memorial, taking a field trip there would not be at the top of your to do list as an educator. Alas, a local class pays the hospital a visit on tonight’s Grey’s Anatomy season 11, episode 18, “When I Grow Up.”

Previously on ‘Grey’s Anatomy’

Meredith and Derek took a wild journey through the story of their relationship this season, but in the end they landed on the same page. They can live apart from one another, but they certainly do not want to. Edwards did her best to get in some surgical hours, while Jo wound up pulling a leech from a woman’s nose and got more trauma time than intended. Owen and Amelia finally, without interruption, got their physical relationship off the ground, while his mother settled back in with her much younger boyfriend.

Related: Grey’s Anatomy season 11, episode 17 recap: Crossing the line

This week on ‘Grey’s Anatomy’

Two cops enter the ER during a field trip and give the students much more than they paid to see. The cops that flood the floor will keep Callie and Meredith busy, while Arizona takes the kids to see the newborns and answer the tough questions about the circle of life.

Watch a preview here.

The kids may be asking the doctors questions, but one parent catches the eye of Edwards. Looks like not everyone will be leaving with the class tonight.

Watch Grey’s Anatomy season 11, episode 18, “When I Grow Up,” tonight at 8:00 p.m. ET on ABC.