• Quick retrieval from earlier learning (How fossils form). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. In how a sea shell becomes a fossil, what happens straight after "a sea creature dies"? (the sediment slowly turns into rock / the fossil is found in the rock millions of years later / its shell sinks to the sea floor / layers of sediment cover it) → its shell sinks to the sea floorPrompt: Fossils form very slowly, buried in rock.
2. In which type of rock are fossils usually found? (lava / metamorphic only / igneous / sedimentary) → sedimentaryPrompt: This rock forms from layers of mud and sand.
3. In how a fossil forms, what happens straight after "an animal dies"? (minerals slowly replace the bones over millions of years / it is quickly buried by mud or sand / the rock is worn away and the fossil is uncovered / the soft parts rot away) → it is quickly buried by mud or sandPrompt: Only the hard parts usually become fossils.

• Pass round different rocks and ask how each one might have formed.
• Share the objective: What fossils tell us about past environments. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: What does this fossil evidence tell us: fossil fish in rocks on dry land?
• Step 1: Fish need water, so water once covered the area.
• Step 2: So the answer is: there was once a lake or sea there
• Answer: there was once a lake or sea there
• Pause after each step and ask a student to say what comes next.

• Do these together. Students try each step on whiteboards before you reveal it.
• Use the hints as prompts rather than giving the answer.

1. What does this fossil evidence tell us: fossil palm leaves and ferns found in Antarctica? (there was once a warm, shallow sea / the rock was once under the sea / there was once a lake or sea there / the land was once warm and wet) → the land was once warm and wetPrompt: Where does that kind of living thing live today?
2. A rock layer holds fossil fish, and the layer above holds fossil land plants. What happened? (Water covered the area, and later it became dry land. / Fish turned into plants. / Nothing changed. / Plants lived under the sea.) → Water covered the area, and later it became dry land.Prompt: Lower layers are usually older.

• Students work on the student sheet. Circulate and check the first two answers of every student early.
• Students who finish: write a question of their own for a partner, with the answer.

The 6 questions are on the student sheet below, with answers in the key.

• Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.

1. True or false? Fossils help scientists learn how Earth's climate has changed. (True / False) → TruePrompt: Where do living relatives of the fossil live today?
2. Why are fossils most often found in sedimentary rock like sandstone and limestone? (Animals chose to die there. / Other rocks are too young. / These rocks form from layers of mud and sand that buried living things gently. / These rocks are the hottest.) → These rocks form from layers of mud and sand that buried living things gently.Prompt: How do fossils start to form?

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-3.