Science Update Pre K - 3rd

Pre-K (GenEd): We have continued to explore our senses, and we have begun reading and thinking about how animals use their senses in ways that are different from humans. We did an activity about our sense of touch where students traced outlines of their hands and glued pieces of differently textured materials to the fingertips of the outlines: a cotton ball for "soft," a square of wax paper for "smooth," and a square of sandpaper for "rough." 

We have been reading from a book about animal senses, and we began by thinking about how animals ears are different from human ears. Some animals have ears that are much bigger than human ears, and many animals can move their ears to be able to listen for sounds. We tried hearing like a fennec fox by poking a hole in the bottom of paper cups and holding them to our ears. We were able to move the cups around to hear sounds coming from different directions. We also read about how some animals use their sense of smell, and how many animals are much better at smelling things than humans are. We used our noses to try to figure out what was in a series of vials. The first vial had a strong, stinky smell, the second vial had a nice clean smell, the third vial had a strong, medicine-y smell, the fourth vial soft, powdery smell, and the fifth vial had a strong, sweet smell. Inside the vials were vinegar, dish soap, rubbing alcohol, baby oil, and peppermint oil.

This week, we read another section of our book about how animals see. We learned that animals see in many different ways, and we tried using different tools to see the way different animals see. We looked through a screen to try to mimic how a bee and other insects see with compound eyes, and we looked through a magnifying glass to see how a fish sees. We also talked about how some animals are much better at seeing in the dark than people are. We passed around a box with four blocks inside of it, and a blue plastic filter on the cover. We peeked into a box through a hole in the side and tried to figure out what color the blocks were. All of the blocks looked blue and black, and when we took the cover off, we saw that the blocks were really red, blue, white and black, and we learned that when we see at night time, it is very hard to tell colors apart.

 

 

Pre-K (SpEd): We have been working with learning to use pipettes. Each student was given a clear plastic plate, a small piece of sponge, and a 50 mL plastic pipette (dropper) to practice moving colored water from the basins to their plates. It can be tricky for little hands to use a pipette, and to remember the steps: if you want to pick up water in your pipette, you have to squeeze, dip, and let go. With practice, we are getting better at moving the water to our plates, dripping it on the plates or on the sponges, and watching the colors mix together.

 

Kindergarten: After finishing our leaf booklets, we had a chance to observe several kinds of leaves that were gathered from Golden Gate Park, and the students made rubbings of their favorite leaves. 

 

After we learned the four parts of a tree (roots, trunk, branches and leaves) and had a chance to take a closer look at leaf shapes, we learned about why leaves are an important part of the tree, and how the parts of a tree work together. We know that plants like trees are living things: that’s why we had to treat them respectfully on our Tree Walk in Brooks Park. All living things need food to grow and stay healthy. Animals eat food, but plants, like trees, are different: they make their own food! We learned that plants like trees make their own food with three ingredients: water, light, and air. Leaves are an important part of the tree because they get the air and the light, and also because they are where the food is made. The roots are important because they get the water the plant needs from the ground. The trunk and branches are important because they take the water from the roots and bring it to the leaves. To help us think about how the parts of a tree work together to make their own food, we did an activity where we were the parts of a tree. We had a big outline of a tree on a piece of fabric, and the students were assigned to different parts of the tree. The root people would get the water, and hand it to the trunk people. The trunk people would pass the water to branch people, and branch people would put the water into the leaf cup where the food was being made. Leaf people gathered sun light and air to put in the food cup. For our three ingredients, we used colored water. Water was colored blue, light was colored yellow, and air was clear. The ingredients were placed in dishes close to the parts of the tree that collect them (water near the roots, light and air by the leaves). Students collected the ingredients with pipettes, and helped transfer the ingredients to the leaf cup, making green food for our tree to use to grow and be healthy. Once we had worked together to make enough food, we used the food we made to help our tree make one of its paper flowers bloom. We played several rounds of the game, and students had a chance to play different roles of the parts of the tree, and with good teamwork, we were able to make several of our paper flowers bloom! (This activity is on display in the kindergarten hallway over the ramp.)

Since we have learned that a tree's roots get water for the tree from the soil, we had a lesson about the importance of healthy soil. We looked at a poster called "Dirt Made My Lunch" (a song by the Banana Slug String Band), we read the lyrics together, and we talked about how every part of the lunch on the poster had originally come from the dirt, and then we talked about what had been for lunch in the cafeteria that day, and we found out about how all of those foods had come from the dirt too. We put together a booklet for the students to take home and share with family and friends about why dirt is so important called "Dirt Made My Sandwich." Each page in the sandwich featured one of the sandwich ingredients: bread, tomato, lettuce and cheese, and on the back of the page was the story of how that ingredient had come from the dirt. Some ingredients had a short story, like bread being made from wheat, which grows in the dirt. But cheese had a long story, because cheese is made from milk, milk comes from a cow, a cow eats grass, and grass grows in the dirt. 

On Halloween, we had a special lesson in the Kinder classrooms, because one of the rules in the science room is that there is no tasting. In their classroom, we played a game about food that comes from trees. I told the students that I had brought in a backpack full of lots of different kinds of foods that come from trees. First, they were going to try to think of every food that comes from a tree, and we would make a list. If the students could think of a food that I didn't bring with me, they would get a point. If I had brought a food with me that wasn't on our list, I would get a point. Then we would have a chance to taste some of the foods that come from trees. Most of the classes were able to think of at least one food that I hadn't brought with me (coconuts, cherries, cocoa beans), but I brought in foods that surprised them, and some foods that they had never heard of. We also learned which foods do not come from trees (a surprise is that bananas do not grow on trees. We learned that trees have a trunk that is woody, and banana plants, although they grow very tall, do not have a woody trunk.) Afterwards, we had a chance to taste some of the more exotic foods. (I brought: apples, oranges, pears, plums, peaches, persimmons, pomegranates, papaya, guavas, figs, dates, mango, avocado, cherimoya, olives, tea, coffee, cinnamon, cloves, and maple syrup. We tasted persimmons, pomegranates, papaya, guavas, figs, dates, avocado, cherimoya, and a drop of maple syrup from the end of a straw.)

This week, we learned about our scientist of the month, and we started talking about another reason why trees are important: many animals live in trees. We brainstormed all the animals that live in trees that the students could think of: birds, squirrels, owls, monkeys, bats, bees, sloths, koala bears, etc. The students completed a worksheet about animals that live in trees. They colored in a picture of a tree and four animals that live in trees: bees, owls, birds, and squirrels. After coloring, they cut the animals out and glued them to their tree. Finally, they drew two (or more) additional animals that live in trees that were not one of the four from their worksheet.

 

Vocabulary: Leaves, branches, trunk, roots, air, water, light

Try this at home: Review how trees (and plants) make their own food. This is one of the lessons where we are able to set a foundation for visible growth the following year, when we discuss photosynthesis in first grade. Students who have had this lesson in Kindergarten and already know the basics of the process are able to expand and refine that knowledge into an understanding of photosynthesis that might otherwise be beyond them. (It is much easier to understand that a plant uses carbon dioxide to make glucose if you already know that it uses air to make food.)

 

First Grade: After reviewing the properties of solids and liquids that we have spent so much time learning about, I introduced the students to five new materials with the challenge to figure out whether they were solids or liquids based on what they knew about solids and liquids. We had five stations, cornmeal, rice, mung beans, pinto beans, and lima beans. The students were given a cup full of the material, a bottle, a large and a small vial, a funnel and a scoop, and they were allowed to touch and play with the materials to try to determine if they were solids or liquids. Most students were able to see that the larger materials (the three kinds of beans) were solids, because they kept their shape, even though they flow and pour the way liquids do. The trickiest was the cornmeal, because the particles were so small that it was hard to see individual pieces, so some students determined that it was a liquid. During our wrap up, we learned that all of the materials are in fact solids, and that if we were to look very closely at a piece of cornmeal with a magnifying glass, we would see that it keeps its shape. Sometimes, when solids are small, they can behave like a liquid (flow and pour), but we also learned some other ways to tell if a material is a solid or a liquid. You can use a plate to find whether a material is a solid or liquid. If you can make a pile of the material, it is probably a solid. If you can draw a picture in the material, it is probably a solid. You can also use another solid, like the metal bolt from our solids investigation, to determine whether a material is a solid or liquid. If you drop a screw into a cup full of material and the bolt stays on top, it is probably a solid. If you stick a bolt down into a material and it stays standing straight up and down, it is probably a solid. 

The following week, we worked with our new materials again, but this time, they were all mixed together. I explained to the students that you can find mixes of beans, rice, and spices sold in a grocery store as a soup mix, and that we had a soup mix made from our materials. However, I decided that I didn't want a soup mix. I wanted to have our materials be separated into their own containers. We discussed how this could be done. Some students suggested that we could separate the mix a piece at a time with our fingers, but we realized that that would be very slow (and probably very boring). Some students were able to think of a strainer, and some even remembered using the screens from last year, when we used them while making paper to separate paper pulp from extra water. I gave the students a set of three sizes of screens and asked them to work with a partner to separate the soup mix into its ingredients. If the students were able to separate the soup mix successfully, we played a game, where they were the chefs of a restaurant who had made a delicious soup mix that was very popular. However, I was a picky customer who didn't like to eat certain foods. I asked the students to make me a special soup mix (beans only, nothing brown, just corn and pinto beans, etc.)

Since we had spent so much time learning about solids, and liquids, and solids that sometimes behaved like liquids, we started to investigate what happens when you mix solids and liquids together. Pairs of students were given a plastic ziplock bag with one of 11 different solids inside (plastic triangle, aluminum foil, cardboard, cotton ball, candy, rock salt, cloth square, corn meal, craft stick, beans, rice). They were asked to draw the solid and to write at least three properties of the solid. This was also a great chance for the students to review the properties of solids. Afterwards, each pair came up and presented their solid to the class and described its properties. We then added a small amount of water to each bag of solids, and we observed how the solid and the liquid (water) changed when mixed together. We saw that some solids changed very quickly (candy, rice, cornmeal), while others changed more slowly or not at all (cardboard, aluminum foil). We did a gallery walk around the room so that the students could see each of the solids interacting with the liquid. I told the students that we would check in with our solids the following week to see how the solids had changed. 

This week, we checked our solids. We saw that some had changed a lot, some had changed a little bit, and some still had not changed at all. We also noticed that when a solid changed, it seemed to change the liquid as well (something we also noticed last week with the candy and the rice). However, some of the solids had become quite stinky and moldy, so we skipped the final step of evaporating the water from the solids. We reviewed the ways that you can tell whether a material is a liquid or a solid, because the final class before Thanksgiving break will be a materials test. 

Since we let out early for conferences this week, and Thanksgiving break starts on Wednesday the following week, this week was our final class. The students were given a brand new material, and they were allowed to observe and experiment with it, and it was their job to determine whether it is a solid or liquid and explain (through writing and drawing) why they think so, keeping it mind what we learned about solids and liquids, and thinking about shape, the plate test, and the metal bolt test. (I told them it does not matter whether they are right or wrong, that it only matters that they show what they have learned and use good reasons.) While they were working on their shaving cream experiment, we also discussed how matter can change from one state to another (solid to liquid and liquid to solid). The example everyone is familiar with is water. We discussed how sometimes, you can change the state of matter by changing its temperature (making it hotter or colder). But there are sometimes other ways to change matter. While they worked individually on the shaving cream, I poured some heavy cream into a jar and went around the room, giving each student a chance to shake it vigorously. By the time class ended, our cream had turned from just a liquid into some liquid and some solid: butter milk and butter. I spread the butter onto small squares of brown bread, and the students got to enjoy them (outside of the science room, of course: no tasting in the science room!).

Vocabulary: matter, solid, liquid, gas, property, plate test, metal screw test

Try this at home: Discuss the different ways that your child can tell if a material is a solid or a liquid. Try giving them some materials that may be ambiguous (sand, flour, elmer's glue, jam), and ask them to think about the ways they can show that the material is a solid or liquid. It doesn't matter if they are correct, only that they can remember and use the reasoning they have learned about.

 

Second Grade: After learning about the properties of our rocks, we began to focus on one property in particular: size. We began referring to our rocks as "earth materials," because we will be thinking about them not just as phenomena that happen to occur in nature, but about the ways in which people use them. We learned about seven different sizes of earth materials, beginning with (largest to smallest) pebbles, gravel, and sand. Since people using earth materials to build things often want earth materials of one particular size, the challenge was to figure out an efficient way to sort a mixture of earth materials that might be collected from a natural source, like our river rocks from a river bed. Students worked with a partner to sort a cup full of earth materials into large pebbles, small pebbles, large gravel, small gravel, and sand. They were given a set of three different-sized screens to help their sorting. In the lesson that followed, we tried sorting again using a new tool: a sorting mat. The mat had a circle to hold each size of material, and a box to compare each piece of earth material by size to determine which circle to sort it into. After having a chance to sort their earth materials with both sorting tools (screens and mats), the students were asked to compare the tools, pick their preferred tool, and explain their preference. Most students preferred using the screens, as it made sorting much faster. However, some students came up with novel answers, like preferring the mat because you can use just one mat to sort all your earth materials, but you need three screens to do the same job-- what great original thinking!

After our introduction to pebbles, gravel, and sand, we read an excerpt from our book called "The Story of Sand," and learned how sand is formed. We added two new sizes of earth materials to our list: boulders and cobbles. We learned from the story that boulders are weathered into cobbles, which are weathered into pebbles, then into gravel, and finally into sand. The question for us to consider then was whether there was a size of earth materials smaller than sand? I asked the students to think about why we had been able to sort pebbles and gravel into large and small, but not sand. They were able to correctly deduce that our screens were not small enough to sort large pieces of sand from smaller pieces of sand (or a material that might be smaller than sand). I told them that we would use another tool to try sorting some sand into larger and smaller pieces, and possibly even find a size smaller than sand. After observing a sample of sand and seeing through our hand lenses that there are, in fact, larger pieces, smaller pieces, and some very tiny pieces, we placed the sand into a vial and filled the vial with water. After shaking vial to mix the water and sand together, we noticed that the sand settled quickly at the bottom, and the water became very brown (students described it as chocolate milk or coffee). We made some predictions about what we would observe if we left the vial undisturbed to settle for a week. Most predictions fell into three categories: 1. The water would weather the sand and the sand at the bottom of the vial would disappear by the next week.

2. The water would be absorbed by the sand.

3. The "dust" making the water dirty and brown would settle back down, leaving the water clear on top and the sand on the bottom of the vial.

After a week, the vials were returned to the students, and we could see that of the three predictions, the third was closest to being correct. The water had indeed cleared, but there was something unexpected with the sand. Instead of two layers inside the vial, there were three. On top of the sand was a thin, lighter layer of brown. This was our new size of earth material, "silt," which is smaller than sand, and therefore took longer to sink because, as the students were able to communicate, the pieces are smaller and lighter.

Having settled the issue that there is a size of earth material smaller than sand, silt, the next question, naturally, was is there a size of earth material smaller than silt? I gave each student a small sample of a material they were all familiar with: clay. They were given time to manipulate and observe the clay, and were asked to think about some properties of the earth material. After their observation, I asked the students to think about where on our earth materials chart the clay belonged. Some students assumed that because each piece was about the size of a pebble, it should go between pebbles and gravel. But we observed that clay can be broken into smaller and smaller pieces. Finally, I told the students that we didn't have the tools to be able to see each piece of clay by itself, because clay particles are so small that they can only be seen with an electron microscope. I showed them an SEM (scanning electron microscope) image of clay particles, which looked like a stack of pancakes. The reason we can see and touch clay is because the tiny pieces stick to each other, and we put that on our list as the smallest size of earth materials.  

Vocabulary: geology, property, basalt, scoria, tuff, weathering, boulder, cobble, pebble, gravel, sand, silt, clay

Try this at home: Our final lesson about rocks will be a rock walk, where we will take a tour of the school grounds and try to find as many examples of the ways people use earth materials to build things as we can. Try to look for examples of people using earth materials around your home or neighborhood.

 

 

Third Grade: If you've been reading Ms. Paige's Science Updates, you have a pretty good idea of what has been going on in my classes as well. After finishing energy transfer, we began to focus on one particular form of energy: light. We have learned that light is a form of energy (and can therefore make things happen, as we saw with our energy station with the solar cell crickets), and we observed that light travels in straight lines from its source, which we call "rays." Several things can happen when a light ray hits an object, and thus far we have learned that it can reflect (bounce off of), be absorbed (soaked up), or be transmitted (go through), depending on what it hits. We began observing how light reflects by doing an activity with mirrors. The students were sent outdoors with a small hand mirror to observe how they could make the light from the sun reflect onto other surfaces. After our outdoor observation, the students worked in teams to try to solve a set of flashlight challenges. Given four mirrors, they were asked to figure out how to get the light from the flashlight to do tricks like shine on the side of the flashlight, or to shine in two different directions at once. 

Following our flashlight challenges, we continued learning new things about light. We learned that light from a source like the sun or a light bulb is called "white" light, and is in fact a "spectrum" made up of all the colors of the rainbow. We viewed light through a diffraction grating that allowed us to see the light being broken up into all the colors. The colors are sometimes known as ROYGBIV (red, orange, yellow, green, blue, indigo, violet), but I told the students that this is just a way to remember them, as there are many more than seven colors, and that we often say that there are seven because Sir Isaac Newton, who made so many important discoveries about light, really liked the number seven. The reason we are able to see colors in objects around us is that when white light hits an object, some of the colors of the spectrum are absorbed, and others are reflected. Since we knew that light going into our eyes is what enables us to see, we realized that when we see a colored object, such as a student's blue sweater, it is because the blue light from the light source is being reflected, while the other colors are absorbed. We also learned that when all the colors of the spectrum are reflected (and none are absorbed), this makes the object appear white. When all the colors are absorbed (and none are reflected), this makes the object appear black. 

To help students understand how light produces color, the students made observations at several stations. Three stations included a shoe box with a hole cut in its lid, covered with a plastic filter, and containing four blocks, red, blue, white and black. One box had a white/clear filter, one had a red filter, and one had a blue filter. The students were given a worksheet and asked to color in the blocks the colors that they appeared when viewed through a hole in the side of the box (this was an important emphasis, as students have a tendency to report what they expect to see, not what they actually observe). With the white filter, there appeared to be a red block, a blue block, a black block, and a white block. Under a red filter, there appeared to be two red blocks (one darker, one lighter) and two black blocks. Under a blue filter, there appeared to be two blue blocks (one darker, one lighter) and two black blocks. At the final station, the students were given a flash light and a set of handheld filters in red, blue and green. They were asked to shine the light first through only the red filter and describe what happened to the light (the filter absorbs OYGBIV, and transmits red). Next, they were asked to shine the light through the red filter and blue filter at the same time. Many students predicted that this would produce purple light, but in fact, most of the light was gone. This was probably the most complicated part for the students to explain of all the stations. First, they had to recall what was happening to the light as it passed through the red filter. Then, they had to think about what happened to the light when it hit the blue filter. The red filter absorbs all the other colors except for red, transmitting red light only to the blue filter. However, the blue filter absorbs all colors except blue. Since there was no blue light reaching the blue filter (it was absorbed by the red filter), and the blue filter absorbed the red light, all the light was absorbed by the two filters, and there was nothing left to transmit. Only combining the blue and green filter transmitted any light, because as we saw with our diffraction grating, a blue filter actually transmits small amounts of other colors close to it (green, indigo, violet).

After reviewing and discussing our observations at each station, the students were paired up and began working on poster presentations about the stations. They were given the format for their title: "Why Does a ________ Block Look _______ Under a ________ Filter?" and told they must use the vocabulary ray, spectrum, absorb, transmit and reflect in their poster. Students will be finishing their posters this week.

Vocabulary: energy, light, ray, spectrum, absorb, reflect, transmit

Try this at home:  Get a pair of sunglasses and have your child try them on. Think with your child about what the sunglasses are doing to the light. Do the sunglasses make colors look different? Why? What do sunglasses do to light?