The Sands of Time Project: Intro to Evolution
Understanding the sequence of deep time is outwardly fascinating, the whisker of time since humans evolved compared to the formation of the Earth. But after the roaring drama of meteor impacts and the crazy, toxic atmosphere of early Earth, it’s easy to get overwhelmed with the detail, particularly as evolution is best taught at the end of a year of life science and we are in our own personal time crunch.
Tempting: Make a great slide show with gorgeous pics of lobe-finned fish hauling themselves out of swamps and looking askance as volcanoes spew lava. I learn so much and feel all inspired, and we ‘cover’ the timeline of life in one day.
This year, I’m trying something more interactive. Here’s their challenge:
Model rock strata and fossils from 4 geologic periods with a soda bottle, sand for the sedimentary rock, ‘ash’ for the mass extinctions, and modeling clay for fossils of the dominant life of each period. Include a deliberate mistake for other kids to find.
Kids are liking it quite a bit and are talking paleantology to each other as the look stuff up on the internet and in their text books. They were so absorbed modeling fossils, making the guide strip, pouring in sand and soil that I didn’t have anything to do. That’s pay dirt right there.
The project is teaching the law of superposition (old stuff at the bottom), fossil formation, sequence of evolutionary events, effects of mass extinctions on biodiversity, finding reliable websites (a particular problem for YouTube clips on evolution, as you can imagine) and interpreting a variety of evolution/timeline graphics they find when they search using Google images. Plus how to work together, with some coaching and quite a bit of leaving them to get on with it.
I deliberately stepped back from “What are you doing? Do this!” and instead circulated twice a period with “How are you doing? Do you need help with anything?”. Clear deadline. Clear instructions. An example at the front and a timeline poster to reference when they did have questions. Project based learning provides a real opportunity for kids to figure stuff out themselves, and to learn the skill of asking for help when and if they need it. I am remembering to respect their ability to do these things. It’s really hard to do, very counter cultural.
Day 1: Introduction to Evolution
Here’s the slide set I used:1. Intro to evolution slide show
I used the extinction rate graph in the slide show to set up the project:
Asked them “What’s the graph saying? Talk to your neighbor.” Then “What’s the red line showing? What’s the trend?” “What’s the blue line showing?” “Which is the dinosaur extinction?” and “Is there a relationship between the amount of biodiversity and the extinction rate?” VERY interesting and surprising to students, especially that we have more species now than at any time in the Earth’s history, and that the Permian extinction was much more massive than the extinction of the dinosaurs. It really whets their appetite to find out more. I was honestly a little surprised that a graph could do that.
I introduced the project just before the end of class. The activity, with student sheets, useful links, some teacher notes and photos of examples is here: The Sands of Time Evolution Project
Day 2: Research and reading. We did crack the textbook for this, and used the iPads especially UCMP’s excellent evolution websites. Q.1 on the sheet guides them.
Day 3 and 4: Planning, doing, drawing, assembling. They did the soil and sand part outside. We collected clear soda bottles for an extra credit point for a week ahead. I nicked the bottles with a box cutter so they could cut the tops off themselves. Use tape to stick the clay to the side of the bottle so the fossils stay visible when sand is deposited on top.
Day 5: The museum show – find the deliberate mistakes, using a textbook Life timeline to help them. Do the follow up questions to link the model to real rock strata and fossils.
It’s tried and tweaked, ready for you to use. I hope you and your students will enjoy it too.
Entry filed under: Class Management, Critical Thinking, Evolution, Inquiry and critical thinking, PROJECTS, Research Skills. Tags: 7th grade science, activity, engaging, fossils, graph interpretation, lab, life on earth, PBL, questioning strategies, science activity, timeline.