In this lesson, students are working towards NGSS standard 1-LS1-1. Use materials to design a solution to a human problem by mimicking how plants and/or animals use their external parts to help them survive, grow, and meet their needs.
Since we have just planted our seeds, it will take a few days for the roots and shoots to grow. While we are "waiting," I build background knowledge about plants that we eat. This gets children thinking about the function and structure of external plant parts. Today we also set up an experiment showing how roots suck water and nutrients up into the plant.
As a warm-up, we'll activate our schema by discussing what plants we eat. Next, we'll read Janet Stevens's book, Tops and Bottoms. I chose this book because it is a folktale that describes plants that grown above ground, below ground, and in the middle (right on the stems). This is such a great piece of fiction, and the book actually is laid out in an up-and-down format. While we read, we'll draw a diagram in our Science Journals of the plants and parts we eat.
After reading, I ask, which of the foods from this book are roots? We ask the question, "Why are roots important?" Finally, we set up an experiment to show how the roots suck up water and other nutrients into the plant.
In today's warm-up, we connect to real world experiences and the plants that we eat. I begin the day with a question:
What plants do we eat?
I ask students to turn-and-talk, and then we share. The turn-and-talk strategy is a great way to get all students engaged with today's concept. As students share, I listen in to see what students know. Then, I call on students and make a list on the wipe board.
Then I ask students, "Which of the plants we eat grow above ground?" I circle them (or highlight them) with a colored marker. I draw a color key at the bottom of the chart. Then, I ask, "Which of the plants we eat grow below ground?" I choose a different color for these items. Then I ask, "If they grow below ground, what part of the plant are they?" It's nice to add a little drama here, "Eww! You mean we eat *roots*!"
We eat many parts of plants, from fruits and seeds to stems and roots. Today we'll look at a few of the vegetables we eat and determine what plant parts they are. Then, we'll focus on the root vegetables and the function of roots.
Before reading, I play a transition song. I use music to help students transition, as it takes every one slightly different times to get ready. Also, my students have the routine that this is the time to sharpen pencils, use the restroom, and stretch their legs a bit! Before playing the song, I say, "By the end of this song, you will need your Science Journals and a pencil at the rug." My students have marbled composition notebooks as dedicated science journals. If you don't have science journals, your students can get a sheet of blank white paper on a clipboard.
In the story, the clever rabbit tricks the lazy bear out of his crops. During reading, I draw a diagram to show where each of the vegetables grows (that is part of the trick!). Students replicate the drawing and labels in their Science Journal. Diagrams are a form of models, and completing diagrams aligns to Science & Engineering Practice #2. Here are some sample student journals #1 and #2 during reading. By the end of the book, our shared writing anchor chart turns out like this, shared writing.
After reading, I ask, "Which of the foods from this book are roots?"
Finally, after reading, I ask, "Which of the foods from this book are roots?" Then I ask the question, "Why are roots important?" This gets to the NGSS standard of the function of external parts of plants. We revisit the objective, to make sure that we met our goals for the lesson.
Next, we set up an experiment to show how the roots suck up water and other nutrients into the plant. I say, "You said that roots help suck up the water. We can put these celery sticks in a cup of water and see how the water flows upwards from the roots to the stem, all the way to the flower! Today we will place the celery in colored water and leave them overnight to see what happens." Note: you can use white carnations or celery stalks for this experiment in osmosis!
Students record the "before" celery in science journals today, then the "after" the following day. Here's a picture of the blue celery the next day, as well as a student journal showing the celery experiment, and a labeled journal after the celery experiment.