The class views recent footage taken by Dive Instructors Mark Poulos and Ben Wilson at the CRWC on Tuesday, April 24, 2018. Both Mark and Ben are fully certified through PADI and work as rescue recovery divers in the local area. (James Year/The Daily Iowan)

Dive Instructor Ben Wilson corrects knowledge reviews from the class at the CRWC on Tuesday, April 24, 2018. (James Year/The Daily Iowan)

Students review course material at the CRWC on Tuesday, April 24, 2018. This was one of the class' last sessions before their open water certification at Lake Pearl, Illinois this summer and focused on dive planning in the classroom. (James Year/The Daily Iowan)

The class grabs their gear and makes final preparations for the practice dive at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Classmates grab their oxygen tanks at the CRWC on Tuesday, April 24, 2018. The tanks are rated at 3,000 psi and can last an hour or more but can vary depending on their breathing rate while underwater. (James Year/The Daily Iowan)

The class prepares to entire the water at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

A student jumps into the water at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Dive Instructor Ben Wilson instructs the goals for the class at the surface of the pool the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

A student poses for a quick underwater portrait at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Dive Instructor Mark Poulos helps a student remove and put on their gear again while underwater at the CRWC on Tuesday, April 24, 2018. This is a very important skill to learn in diving in the event that a diver gets snagged in debris, nets, or other types of underwater hazards. (James Year/The Daily Iowan)

A student tries blowing bubble rings while waiting for individual instruction at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Students enjoy a brief period of free swimming at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Students play rock paper scissors while waiting for individual instruction by Divemaster Mark Poulos at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Students enjoy a period of free swimming and play games to hone their skills underwater at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Dive Instructor Ben Wilson (center) lines up the class to help demonstrate essential dive skills at the CRWC on Tuesday, April 24, 2018. Students are required to show they are proficient in a number of skills directly to their instructor to prove they can dive safely. (James Year/The Daily Iowan)

Dive Instructor Mark Poulos demonstrates how to inflate dive buoys at the CRWC on Tuesday, April 24, 2018. The buoys are used to show a divers location to nearby boat traffic. (James Year/The Daily Iowan)

Students enjoy a period of free swimming at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Dive Instructor Ben Wilson blows some bubble rings for fun during a free swimming period of the class at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)

Student divers ascend to the surface at the end of class at the CRWC on Tuesday, April 24, 2018. Students are expected to continually exhale during the ascent to prevent lung over-expansion injuries. (James Year/The Daily Iowan)

Students finish the class and prepare to exit the pool at the CRWC on Tuesday, April 24, 2018. This was one of the class' last practice sessions before their open water certification at Lake Pearl, Illinois this summer. (James Year/The Daily Iowan)