Teaching Observations and Inference in Science

I love middle school. But they think so quickly that they don’t necessarily think about what they are thinking! In science specifically, they have to know the difference between an observation and an inference. Their observations lead to their inferences and generally serve as evidence for their inferences.

To introduce this idea, I give them that “angry teacher” stance and eyes and ask them how I am feeling. Without fail, they tell me that I’m mad, angry, upset, that they want to run away and hide (HAHA!!)… and a few will say my arms are crossed or I’m not smiling, but usually not without some prompting asking them how they know I’m angry.

They can tell you clearly that I’m upset, but I need them to break it down and use their observations as evidence for their inferences. 

Keeping this in mind, we added a page in our notebooks differentiating between an observation and an inference. These notes are quick, simple, and to the point. I love their notebooks because it means they have the information in their possession for the rest of the year!

Next, I told them that I took a trip this summer with NASA to another planet and managed to grab some soil samples for them to examine. I needed to find out what life is like on that planet. Since we can’t see the planet, we have to use our observations to create inferences. (How many of them asked me later if I really went to another planet?! HA!)

I modified this from NASA’s Mystery Planet Activity to fit a little better into my classroom.

I make enough soil samples for about 16 groups. This activity is best done in pairs so students get enough hands on time with the soil sample. I made the soil sample with:

From my backyard:  Dirt, gravel, leaves, sticks, and tree bark.

From Hobby Lobby: A couple of feathers, smooth river rocks, the sea glass looking rocks, shells, and a broken terra-cotta pot.

From around my house: A button or two, the plastic pull that seals the milk, a bottle cap or any other odd knickknacks.

Try to only put the man-made objects in a few soil samples. I didn’t want to give everybody a man-made objects because they end up being more curious when all the soil samples aren’t the same. For example, I only put a bird feather in one soil sample. I found a bone on the beach, so one soil sample had that. Be creative.

We go over the definition of an observation versus an inference in their notebook one more time, then I give them their soil sample, two popsicle sticks for sorting, a magnifying glass, a grid paper, and several index cards (you could easily cut the index cards in half).

I give them about 15 minutes to sort through their soil and and write down observations of their soil onto the T-chart on their notebook. They do not write inferences on the other side yet. During this 15 minutes, they have to write two inferences on notecards in one color. Then they choose any observation that helped them make that inference and write those on note cards in a different color.

As a class, we talk about the different observations they have as I write them in my notebook. They add everything they didn’t write, even if they didn’t have it in their soil sample. After several groups have shared out their observations, they start to tell the inferences they came up with and the observations that led them to those inferences. We write them into out notebooks and discuss them along the way.  (Note: When “humans” come up as an inference, I ask them if they observed humans in their soil sample or if anything explicitly made them KNOW it was humans. They always say no. I explain that we know an animal didn’t make a bottle cap or a button, but we can’t necessarily assume it’s humans. We refer to “humans” as Intelligent Life.)

Finally, I ask students to answer this prompt:

Discuss two inferences you and your partner came up with about this mystery planet. Use at least to your observations to prove those inferences. Explain how those observations led you two those inferences.  

They can manipulate their observation notecards by moving them to support their inference card before they write. Moving the cards to categories helps them see how the observations connect to the inferences. It’s possible they’ll see how inferences can create more inferences – if there is a bird, there must be water because birds need water.

The paragraph is a quick check for me and helps cement the idea of observations supporting their inferences rather than jumping to conclusions without support. This is such a fun activity to teach a rather simple concept.