Underwater Writing Devices
Depending on the types of activities you are going to do (and how often you will be doing them) you might like to invest in underwater slates or clipboards. This means that while students are snorkelling they can be taking notes - perhaps about their location, types of organisms, or number of species observed or a particular underwater geological feature.
View underwater writing devices:
Dip N Dive - Under Water Writing Devices
You may also like to use an online field guide such as:
Marine Life Identification Guide from Snorkeling Report.
However, keep in mind that you probably don't want students and teachers using their phones/laptops while wet or near the water, so this might be more useful for checking fieldwork results back in the classroom.
A simple quadrat square can be made from pvc piping and corners, to use to do quadrat sampling.
Students gently lay down a quadrat square underwater (being careful not to disturb anything growing). They can either take a photograph to examine later or make notes about what they see within the square. For example, they might make note of the number of seaweed or seagrass species within the square, or the number of sea urchins within the square, or the variety of species. This activity should be repeated a number of times. Students can determine average calculations of a general location and then compare it with another location, or repeat the activity at another time to determine change over time.
Measurements and colour analysis
Students can use a ruler and colour chart to explore corals, seagrasses or seaweeds. In the case of corals, colour is an important indicator of coral health.
Underwater photography and videography
Students can easily take photographs and videos of the fieldwork site. These can be shared and compared with their classmates. In-built GPS will help to geotag the photos, or a GPS logger can be used. Photos and video can be used to identify different species, examine data on abundance of species, or explore human impacts. Photos can be added to locations on digital maps using Scribblemaps.
There are a couple of relatively cheap underwater cameras you can buy. Be prepared - if they are used regularly, they will get broken, and most likely they get water in them (also meaning they will be broken). I have bashed more underwater cameras into rocks than I care to admit. There used to be a wide variety available, but there aren't too many on the market these days. If you are going to get a student to take photos, make sure you get a wrist guard with a floatation device attached in case they drop it. Another good option to to use a hair elastic attached to the camera strap to that it doesn't get lost. For around $600-700 you can get basic model underwater camera from Olympus: Olympus TG-6 Tough Underwater Camera (Black). There are lots of other options for underwater cameras available, but they tend to be very expensive.
Probably the easiest option is to use a GoPro, with a waterproof case attached with either a velcro wrist band or a strap around your chest or head. Even though the GoPro11 is advertised as waterproof, I was advised to also get a waterproof case. There are also some masks that you can buy so that you can attach the Go Pro directly to the mask.
GoPro HERO11 Black Action Waterproof Camera
GoPro Protective Housing
GoPro Hand + Wrist Strap
Body Glove Adult's Arid 2 Piece Set Blue & Black
Students can use a basic outline map of the field site to demonstrate features which relate to human impacts on the reef. Students might mark on a map stormwater drains, stairs or entry points, boat ramps, pools, jetties, etc. Students may use the map to identify where they observed particular species in the field site. Students might map areas of natural vegetation surrounding the field site.