Umbrellas are not be carried by students. Here are the words from the handbook on page 32.
Finally, students should have rain gear stored in your their locker and left there for rainy days. In the event of thunder/lightning, students will not go outside; however, steady rain will not cause cancellation of outdoor activities. Due to safety issues, students are not allowed to carry umbrellas. Recommended rain gear includes a good rain jacket (that can layer over a warm jacket in the event of cold rain), rain pants, and rubber boots.