Finally... How I introduced 8th graders to aquatic ecology

In my last post, I talked about my trip to the pond in preparation for outreach to a group of students.  I wasn't completely sure what to do with them (they were learning about biomes and habitat) since their teacher gave me a really broad idea of what she wanted.

So, with a few loose ideas in mind, I loaded a lot of show-and-tell type stuff into my car and headed off on a 90 minute journey to a very small town in Oklahoma (so small that I passed the school completely the first time around).

The science classroom was fairly well equipped - they had a separate "lab room" with sturdy lab benches and microscopes.  Once I saw the space and the number of students, I decided to set up learning stations (for the uninitiated, I do not recommend going in without a firm plan).

Anyway, the six learning stations were as follows (no particular order):

Flotsam and Jetsam: Here I put out random things from the ocean - some mermaid's purses (skate egg cases), a weird isopod molt from Japan, a couple of deceased hermit crabs (one in shell and one out of shell), various shells and barnacles.  I also put out a number of tide pool books and golden guides to the seashore, seashells, etc.  Believe it or not, the students were very excited to identify the miscellanea using said books.

Freshwater/Saltwater:  I set out various clam/mussel shells from the seashore alongside freshwater mussel shells (clams) so that students could make comparisons among the different shells from organisms that have similar function (filter feeding) in different habitats.

Ancient Aquatic Habitats:  This station allowed students to compare modern clam and limpet shells (both marine) with fossils from Calvert Cliffs, MD and Southeastern OK.  Since OK was once covered by a shallow sea, the forms of the fossil shells are very similar to the fossils from Calvert Cliffs and modern oceans.

Microscopic Life:  This is my specialty.  We set up three microscopes where students were able to view living plant tissue, live rotifers, and a cladoceran (which was fortunately stuck in place for some reason).

Macroscopic Life: This is where the pond water mentioned in the last post comes into play.  Students were able to isolate aquatic invertebrates on styrofoam plates (it gives just enough water for the invert to move around, while allowing the students an opportunity to observe them rather closely).

Constructing a Habitat: With my giant water bug, "Buggy" (so named by another group of students) as an example, students set up their own aquatic habitats with mud, gravel, plants, pond water, and aquatic inverts.

Afterwards, we chatted about things they noticed and I pointed out form and function (grazers, shredders, predators, filterers).  We also talked about animal shape and how water flow (rivers, waves, tides) can influence shape.

They asked some really great questions too - like why there are zebra mussels in the lakes.  They were a very mature group as well.  We were talking about how mussels feed, which involved talking about the location of the mouth and anus, strategically located such that mussels do not end up eating their own feces.  The only one who giggled was their teacher, who was chastised by her own class!  I think my most interesting question came from a student who wanted to know how mussels "do it" (we were talking about life cycle in response to the zebra mussel question).

I feel like I passed some sort of test with that one.  "Explain mussel sex to eighth graders... check."