Rocks, Fossils, and the Law of Superposition Sequencing Activity


  • Sequence information using items which overlap specific sets
  • Relate sequencing to the Law of Superposition
  • Show how fossils can be used to give relative dates to rock layers.


  • Fossils, Rocks, and the Law of Superposition Google Slides – this will walk you through the lesson step-by-step
  • Set of 8 cards for each groupsdownload from the UEN
    • additional lesson plan details on their site
    • print and cut apart the 8 cards for each part of the lesson
    • to set up the cards, use large 4×6 index cards and store in ziptop bags.
    • on one side of the index cards, glue on the nonsense letters
    • on the reverse side, glue on the fossil layers
      • laminate for durability
      • Replace the letters for each fossil layer, see my ppt for new random letters
        • spelling out the word “ORGANISM is way too easy for students to figure out and they will not really have a chance to work on the activity with the depth of thinking and problem solving that you want them to do
        • be sure to stagger cards so that the order of the cards is not the same, otherwise they will flip over the cards and have the answer for part 2
  • Notes HandoutLaw of Superposition Notes (pdf) students will take notes and record their answers on this handout.

Tips for this lesson:

This is a fantastic lesson and I have used it successfully with both 5th and 6th grade students. When introducing this lesson I use the analogy of a laundry hamper, or in most cases, the pile of dirty clothes on the floor in their bedroom. Today’s clothes would go on top of the pile, each day adding a layer of dirty clothes. The older clothes would be on the bottom of the pile, kind of like a timeline of what they wore this week. When that laundry is collected and moved to the laundry room, the layers would get disrupted. With rocks, the layers form on top of each other, and the older layers are on the bottom. We then brainstorm how those layers can be disrupted: earthquakes, tectonic plates moving, landslides, digging, etc…

For this activity, they have to figure out the pattern of how these layers are formed, and there are clues in each layer, they just need to know what to look for. For the nonsense letters, there is a pattern that connects all the layers together. Many will think it is alphabetical, but I tell them that it is not. Once they have worked on it a few minutes, I have them share their theories. Once each group has shared their theory, I give them the clue. And suddenly, the pattern is clear now that they know what to look for. Using the same strategy, they will then sequence the fossils on the reverse side of the index cards.


Sugar Density Column



  • Student Handout (pdf)
  • Food Coloring – Red, Blue, Yellow, & Green
  • Erlenmeyer flask filled with warm tap water
  • Graduated cylinder
  • 4 Stirrers/Sticks
  • 4 Pipettes
  • 1 Spoon
  • Granulated Sugar
  • 3 Test Tubes
  • Test Tube Rack
  • 4 Clear Cups

This sugar density activity is one I have never tried before, I actually ‘borrowed’ the idea from my son’s HS Chemistry Teacher. He came home and told me they made different colored layers using only sugar, food coloring, and water. I immediately jumped on the computer and thought about how to use this in my 6th grade classes, we are in the middle of our density unit and it would be a perfect opportunity to try it out.

Materials for the Experiment

One of my goals for this year is re-examine my lessons and see which activities I can make more open-ended when appropriate. For this activity, most of the resources I found told the students exactly how much sugar to put in each layer and what order to place the colors into the test tube or some other type of container. I didn’t want my students to follow step by step procedures, but wanted it to be more of an exploration type of activity. I had no idea how this would turn out but gave it shot anyway.

I gave them the problem, the parameters, the tools to complete the activity, and sent them on their way. It was great to see them figure out how to solve the problem, talk out strategies, and to see them go through the trial and error process. Each group came up with a different way to solve the problem and some groups struggled more than others. I met with each group to facilitate, ask questions, and had them explain to me what they were doing and why. Overall, it was a successful lesson, they enjoyed the activity, and it really solidified their understanding of density.

I am also incorporating more open ended writing in science and I enjoyed reading their reflections about the activity.


Task 11 – Layers of the Atmosphere

Image Source: Windows to the Universe
Image Source: Windows to the Universe

Task 11: Adopt A City – Layers of the Atmosphere

  1. Record today’s Weather, yesterday’s Hi/Lo/Precipitation, & Astronomy Data (link) (excel).
  2. On your mini-map (pdf) record the following:
    1. WSM – add it to the classroom map of the USA (pdf)
    2. Precipitation (Rain – green, Snow – blue)
    3. H/L/Fronts (link)
  • Use the resources below to learn about the layers of the atmosphere and complete your notes (pdf).
    • Study Jams – Atmosphere (link)
    • BrainPOP – Atmosphere video (link)
    • Weather Guide pgs. 34-37 & 44-47
    • Interactive – where does it go? (link)
    • Layers of the Atmosphere NOAA (link)
  • Once you have completed your notes (pdf):
    • Complete the illustration by adding an object to each layer and color each layer lightly.
    • Add the miles to each layer.
    • Can you add the Ozone Layer and the Ionosphere to your diagram?

Adopt a City Unit (link)