## Cabbage Juice Lab – pH indicator

My students have enjoyed the Cabbage Juice Lab over the years – and yes, it does smell!

Materials per group of 3-4 students:

• Student Handout (pdf)
• Cabbage Juice in an Erlenmeyer Flask with a pipette
• micro-wells or small clear bathroom cups
• litmus paper – blue and red
• toothpicks
• ‘garbage’ cup
• beakers and pipettes for each solution
• Substances to test – diluted in water
• You can have all of these set up at one station and students can pick one up and take one to their desk for testing, then return it to the station and choose another substance- you don’t have to have a complete set for each group.
• vinegar
• lemon juice
• lime juice
• pickle juice
• baking soda
• salt
• sugar
• detergent
• hand sanitizer
• alka seltzer tablets
• bleach
• ammonia

## Rainbow Test Tubes Activity

Problem: How many colors can be created by starting with red, yellow, and blue solutions?

Updated Jan. 10, 2017 with results:

Materials per group of 3-4 students:

• Student Handout RainbowTestTubesPublic (pdf)
• Spreadsheet to collect data (excel – public)
• 9-10 test tubes with test tube rack
• Erlenmeyer flasks filled with red, yellow, and blue solutions of food coloring and water
• 5 drops of food coloring per 200 mL (25 per 1L)
• 3 x 25 mL Graduated Cylinders
• 3 x 10 mL Graduated Cylinders
• pipette
• beaker filled with clean water
• large beaker for used water
• this activity took 2x 50 minute class periods

This lab is an updated version of the classic Rainbow Lab (link) that has been around since the 80’s (Measuring Liquid Volume with a Graduated Cylinder 1988). I used this for many years with my 5th graders, and previously with my 6th graders in the early 2000’s. Now that I am teaching 6th grade again, I wanted to make it more open ended and challenging. The purpose of the original version of the lab was twofold: First – could they follow directions carefully to make a rainbow? Second – how precisely can they measure liquid volume?

For the new version of this lab, I created new objectives and assessed the students based on their problem solving, collaboration, and measuring skills.

Objectives:

• Students will be able to precisely measure liquids with a graduated cylinder
• Students will be able to create their own lab procedures using the given parameters to guide them
• Students will create new mixtures and solutions
• Students will be able to record accurate data
• Students will collaborate and problem solve to achieve a common goal
• Students will test, evaluate, and select the best proportions to create the colors orange, green, and purple
• each group made 3-4 different combinations for each color and had to, as a group, determine which combinations of primary colors created the best secondary colors
• Students will follow proper lab procedures to avoid color contamination
• Students will record and analyze data from the whole grade and compare their findings to the averages from each group, what patterns or trends did they notice in the data?
• Students will create their own ‘designer’ color and share it with the class
• this was fun way to wrap up the activity, we had a ‘fashion’ show with each group coming up to the front of the room to showcase their newly created and named colors
• if time allowed, at the end we made a rainbow with each student holding their test tube and standing next to a person who had a color similar to their own, from Red to Purple

## DNA – Paper Protein Chains Activity

Purpose:

• Students will convert their name into a DNA sequence and create a protein chain.

Materials:

• Student Handout (DNAPaperProteinChainsActivity)
• pre-cut 2 inch wide strips of construction paper  (12×18) in the following colors – red*, pink, yellow, orange*, green, lt. blue, dk.blue, and black*
• (*) be sure to have more of these colors since they are vowels
• I used a paper cutter and was able to make a lot of strips very quickly ahead of time
• markers
• staplers
• clothes pins and string to hang up in classroom

Procedures:

1. This activity should be used after DNA and protein synthesis has been introduced. This activity will help reinforce the concept of how the sequence of DNA codons create specific amino acids, and in turn, the amino acids are joined together to create specific proteins. (link)
2. Each student will write the letters from their first and last name onto the student handout.
3. Using the chart, they will find the amino acid associated with the first letter of their first name.
4. For example, if the first letter is “L”, it will code for Leucine. They will select one of the codons for Leucine and write it on their chart.
5. Write the color of the paper link they will need for “L”, in this case, it is Red.
6. Repeat for every letter in their name.
7. Once their handout is completed, they will select the colored links, one for each letter of their name.
8. The colored links will be placed in the same order as the letters in their name.
9. On each link, write one of the codons for that letter. For example, “L” would be “CTT” on a Red link.
10. Loop and staple the first letter of their name.
11. Weave through the second letter and staple the loop closed.
12. Continue until all the letters have been linked together.
13. Hang up the protein chain, be sure to have the first letter of their name at the top.
14. Look for patterns – what color was used the most? Which group of amino acids was it? Which group of amino acids was used the least? Who had the longest name? Etc.

## Sugar Density Column

Materials

• Student Handout (pdf)
• Food Coloring – Red, Blue, Yellow, & Green
• Erlenmeyer flask filled with warm tap water
• 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.

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.

## Super Easy to Make Cartesian Divers

This was the easiest, and most inexpensive way to make cartesian divers I have ever tried, and each student got to take theirs home after class. Did I mention how much fun it was?!

Materials

• semi-transparent to transparent bendy straws – 1 per student
• colored paper clips – 4-6 per student
• scissors – 1 per 2-4 students
• 2L bottle with cap – 1 per 2 students
• beaker of water – 1 per 2-4 students
• tray to contain spills -1 per 2 students
• paper towels
• optional: eye dropper with blue colored water

Part 1 – Demonstration:

As part of our density unit, we talk about the concept of buoyancy – why do objects float or sink? Using a 2L bottle of water, a glass medicine dropper, and some blue food coloring, we made guesses and observations about the cartesian diver.

The medicine dropper is filled with blue water, checked for buoyancy, and then added to a 2L bottle. Students gather to make observations. What do you think will happen when I squeeze the bottle? What will the blue water do? Why did it sink? Why did it float? What is happening to the air in the diver? What is the water doing? Did the mass of the diver change? The density? Students share their ideas and we come to a conclusion as to why the diver floats and sinks.

Part 2 – Build and Explore:

After the demonstrations, students get to build their own divers and explore on their own. Some tips to keep in mind:

1. Be careful bending the straw, any cracks will make the the straw useless.
2. After bending the straw, cut off the excess length of straw so that both side are equal in length. (You can save the rest of the straw for future activities)
3. Attach one paper clip as shown in the diagram below. Additional paper clips can be easily added or removed by sliding them on or off the main paper clip. (Like keys on a keychain)
4. Use a rescue hook for any divers that do not float back to the top.
5. Remind students to place the cap back on the bottle TIGHTLY – or water will shoot out of the bottle when they squeeze it.
6. Lunch or serving trays work nicely to contain spills.

## Triple Beam Balance – Bottles of Stuff!

Materials

• Single Serving Size (1L or less) bottles filled with various items
• students brought in materials of their choice over the course of a week
• Triple Beam Balance (TBB)
• Mass Set
• Student Handout (Triple Beam Balance Bottles pdf)

Procedures – Part 1

1. Provide each lab group with an assortment of bottles
2. Students will arrange the bottles from lightest to heaviest by making observations
3. They will record the order of the bottles and their contents with #1 as the lightest and #10 the heaviest on their handout
• my groups used 9 bottles, but there is room on the handout for 10
4. Using the set of masses, they will estimate the mass of each bottle by holding a bottle in one hand and a mass in the other hand, recording their estimations on the handout

Procedures – Part 2

1. Students will transfer their estimation to the back page
2. Using the TBB they will record the actual masses of the bottles
3. Then they will rank the bottles from lightest (#1) to heaviest (#10) and compare their estimation to the actual masses. How close were the estimations to the actual masses? Did they place the bottles in the correct order?

Results

 Bottle # Mass (g) Bottle # Mass (g) Bottle # Mass (g) 1 126.9 14 281 27 192.3 2 72.9 15 336.5 28 330.9 3 29.6 16 223 29 465 4 438 17 70 30 195 5 202.1 18 36.43 31 59.1 6 166 19 185 32 168.8 7 63.1 20 88 33 33 8 301.5 21 140.1 34 100 9 224 22 49.1 35 402.5 10 610+ 23 73.3 36 187.1 11 67.1 24 54.9 37 318.4 12 251.8 25 27.5 38 13 410.1 26 406 39

You can also use these bottles as part of your density unit, see my blog entry for more information.

## Density Bottles Demo

How to use density bottles:

Demo & Discussion – For this part of the lesson, students will not handle the bottles, they will answer discussion questions based on their observations only.

1. Share observations about the bottles.
2. What do the bottles have in common?
3. What is different about the bottles?
4. What do you think the original contents of the bottle were?
5. What phases of matter are shown?
6. Are any of these bottles empty? Explain.
7. Do all of these bottles have air in them?
8. Which bottle has more air in it: Cotton Balls or Water? Explain.
9. Which bottle is filled the most? Least?
10. Which bottle has has the most ‘stuff’ in it? Least?
11. Which bottle is the heaviest? Lightest?
12. How would you order these bottles from lightest to heaviest?
13. Estimate the mass of each bottle in grams.
14. Which bottle is the densest?
15. How would you arrange these bottles from least to most dense?
16. Which of these bottles can have more of the same ‘stuff’ added to the inside of the bottle? Explain.
17. Which bottle(s) would float in a tank of water? (I do this at the very end of the lesson with everyone at the sink)

Hands On Exploration

1. Each group will have one set of bottles or take turns using the demo bottles and sharing their findings.
2. Using a triple beam balance, the volume of the bottles, and a tank of water, answer as many of the questions above as you can. (for our calculations, we use the volume of the bottle’s original content (500 mL of sport drink) to give us an approximate density, not the actual density – for comparison purposes only)
4. Dunk tank – time to find out which one will float!

Further Exploration

Give each group of students a new set of bottles (ones that they have brought in from home) and have them make observations, predictions, and density calculations.

• Rocks/pebbles
• laundry detergent – liquid or powder
• paper clips
• paper shreds
• crayons
• marbles
• flour
• coffee beans
• beans
• different shapes of pasta
• pom-poms
• pop corn kernels or popped
• Lego pieces
• salt
• dish-soap
• yarn/string
• etc…

Have each student bring in a bottle from home filled with the contents of their choice so that you have enough bottle to compare. Match similar bottle shapes/sizes together for each group or match similar contents in different sized bottles for comparison.

You can also use these bottles as part of a Triple Beam Balance Activity (blog entry).

(For lessons and resources on finding volume using water displacement, please see my earlier blog entry)

3. Common Core Worksheet – link
5. Super Teachers Worksheet – practice problems (pdf)
6. Science Starters/Warm Ups/Do Nows: (Graduated Cylinder ppt), (Beaker/Erlenmeyer ppt)

Tips:

• The graduated cylinder has markings, like a ruler, to measure volume for water and other liquids
• I like to use food coloring and water for the students to practice their measurements, it makes it easier for them to read the values, plus it adds some pizzazz to the lab.
• I mostly use either blue or green food coloring, the red can stain, yellow is not dark enough.
• Place all materials on a lunch tray for each group to contain spills and make for a very easy clean up.
• Glass graduated cylinders can break if knocked over, plastic is more durable but can be harder to read.
• Have students explore how to use read and use graduated cylinders:
• Students can explore handling and pouring water into the graduated cylinders and reading the values.
• Once they have mastered pouring and reading, they can practice measuring specific volumes such as 10 mL, 20 mL, 42 mL, 58 mL, etc into the graduated cylinder.
• You can also set up stations with pre-measured graduated cylinders and have them practice reading the volumes.
• Have cylinders of different sizes and increments to make it more challenging.
• You can place task cards/answer keys at each station so students can self check once they have made their readings for immediate feedback.

## Finding Volume of Rectangular Prisms Using Length x Width x Height

Materials:

• Handout – Volume Lab (pdf)
• This handout includes a pre-lab assessment and answer key
• Rulers
• Calculators
• Blocks (set from Flinn)
• I use these blocks as part of a density lesson as well
• Prior to this set, I used blocks of scrap wood that were cut in the wood shop, but any rectangular shape works well such as chalk boxes, expo boxes, staple boxes, tissue boxes, playing cards box, dice, etc…

Background

Prior to having the students record the measurements for the blocks, we go over the importance of how to orient the blocks before measuring. A problem that students often run into is that they end up measuring one of the sides two times, and not measuring all three of the sides. Even though the right-hand rule is not used for volume, it helps to find the L, W, & H of each block.

In the image below, Z = Length, Y= Width, and X = Height. Mathematically, it doesn’t matter which side is designated as the width, height, or length since all three sides are multiplied, but this will help students measure all three sides properly. Students should place the block in their hand and align their fingers with the three sides of the block. Once they have decided on how to orientate the block, they can record their measurements.

For this lab, you can have several stations set up around the room with 1-3 blocks at each station. I assign each block a number and using a black sharpie, write it right on to the block itself. Not all blocks have to be measured, once each student has measured 10-15 blocks, they can go back to their seats and compare their measurements with a partner. We go over the answers together as a class once everyone is done.

1. BrainPOP – Measuring Matter (link)

## Hurricane Season: Lessons & Resources

Updated August 2016

We are heading into Peak Hurricane Season, with forecasts predicting 12-17 named storms. Using the resources below, students can track Tropical Storms and Hurricanes, as well as learn about how hurricanes form, the parts of a hurricane, the difference between a tropical storm and a hurricane, and the intensities of hurricanes with this mini-unit from my Adopt-a-City Weather Unit (link).

Hurricane Resources:

• Hurricane Notes (pdf) –
• How are hurricanes named?
• Which storm was more destructive, Katrina or Sandy?
• Choose any one Hurricane and plot it on the NOAA/NWS Atlantic Basin Hurricane Tracking Chart (pdf)
• Practice latitude and longitude: plotting hurricanes worksheet (pdf)
• Hurricane Isabel 2003: tracking and analysis of Hurricane Isabel (pdf)
• this website needs a subscription to view video and activity

View Current Activity using WunderMap: https://www.wunderground.com/wundermap/

1. Layers: Click on Tropical – deselect any other layers to make map less cluttered for now
2. Check the box next to Hurricanes/Typhoons to view activity for the US
• The Legendtab will show Hurricane categories
• There may not be any activity today
3. Check the box next to Sea Surface Temperature to view ocean temperatures

Interactive Activities