Color Mixing with RGB LED #1754


#21

If you are looking for different boards or setup, I have had great success using a similar setup like the one used for the Sparkfun Inventors kit. Just having the boards mounted next to each other makes wiring a little easier especially for the younger students. I like to make stuff and use the toys in my classroom, so I am going to cut some acrylic and rivet the boards to it. A bigger board would make things a little easier as well.


#22

Hi Rhonda! As far as I know, they make longer and wider breadboards but not ones with bigger holes :(. If you find one though, let me know (I will do the same)!


#23

Rhonda, it sounds like the experiment worked exactly as it was supposed to from your description. What the potentiometer does is controls the blinking rate between the color changes. You should have noticed that it gets faster and faster and faster and then suddenly stops and turns white. What has happened is the colors are still changing but they are blinking so fast that your eyes can’t detect the blinking and all three colors “mix” and appear as white. Additive color mixing of RGB leads to white!


#24

I love this so much–we would love to see video or a photo if you are so inclined to share!


#25

Hi everyone,

Where does this lesson fit in with your curriculum?
This is an excellent experiment to pair with a unit on light and visible spectrum, such as in Physics Earth Science, or Astronomy.

Which part of the lesson would your students need extra support?
I am color blind, and this exercise was a bit of a struggle for me, so if a student has the same limitation I can see having some trouble figuring out color mixing. However, the RGB values in the code are very helpful in coping with this, as they represent an objective way to control the colors.

What does a successful teacher actively do during this lesson?
I would assign this as a project and have students develop a simple real-life application using this sketch. A teacher would have a facilitator role.

What does student success look like?
Using this exercise to develop a simple application to a daily situation is good evidence of success for students.

Thanks,
Gianluca


#26

Jill,

I have had similar difficulties with pin locations. I need a magnifier glass in order to connect pins and I will have to get some for my students as well next school year.

Gianluca


#27

Where does this lesson fit in with your curriculum?
This may be my favorite lesson yet. I think my middle schoolers would love this. While coding is not part of my normal course curriculum. it provides some easy to follow coding for students to explore color. I can see this as part of unit on the eye in my 7th Grade Life Science class.

Which part or parts of the lesson would your students need extra support to be successful?
The wiring is a challenge. I found the four prongs of the LED difficult it place of the board. Also the pins of the pins of the potentiometer were hard to place with the wires so close to it. In the picture, it looked like the pins of the potentiometer were to one side not in the middle.

If you were to teach this lesson to your class, describe your role during the class. What does a successful teacher actively do during this lesson?
I would have to help set-up the board for students who did not have the manual dexterity to place the pins in the correct places. I would have them instruct me how to do it, but do the physical part for them.

If you were to teach this lesson to your class, describe your student’s role during the class. What does “student success” look like?
Students could explain why we see the colors we see.


#28

Good point. I hadn’t thought about the impact on people who are color blind. I have some students who are color blind. Perhaps there is a way to parlay this into a lesson on color blindness so that other students have a better idea of the impact of having color blindness.


#29

A suggestion: Once you use the magnifying lens to identify the correct positions, maybe use a sharpie marker to mark the correct holes with a bright color that is easier to see and aim at. LOL That was my solution. I think students will see it better than we do, but since I just passed off my eye exam last week, I know my close vision is not that bad, yet. :joy:


#30

This fits right in with the extracurricular projects I do with my students. We are always trying to tech-up holiday decorations. I will also bring this into my computer applications class. I think the students will be able to handle this without much support. This is a great way for them to understand how monitors work. This is one lesson that I can let the students explore on their own. Success will look like students having fun with colors!


#31

I already teach a lesson around Christmas time about RGB in relation to choosing colors for coding using a RGB identifier. I can easily dove tail this experiement with that lesson, and I feel like this experiment will add to that lesson and make it easier to understand. It was quite fun changing the numbers top mix colors and see what you get.

Since my kids already have some basic programming experience, I don’t think there will be much extra help needed. Setting up the circuits might be a little tricky, but I will use the document cam to demonstrate the process and I don’t anticipate much of a challenge. I could see when the art teacher is teaching the color wheel and try to coordinate this lesson in the same time frame.

Success will look like students having fun experimenting with color and understanding how light mixes to make colors. It might be fun to bring in a prism to split light too, so they can see that color creation goes both ways.


#32

That’s a great idea. I do a lesson around Christmas time where I take several winter themed images and then use a photo editing software to zoom in to the pixel level. I use this lesson to teach students that everything a computer displays is really just a series of colored dots. This lesson has served me well as an easy one right before winter break when kids are so anxious for break that they can’t focus on anything more complex than that anyway. I think using this experiment to make a light show would be fun.


#33

I don’t understand the rgb values used here. They seem to be backwards from what I would expect. If I use an online rgb chart to make purple, I find rgb(128,0,128)- but on the arduino I have to use 255 instead of the 0 … Why?

Other than that - I like the experiment. I think I might have a breadboard somewhere that has labels that I can actually read. With my glasses on and with a magnifying glass in hand, I still struggle.

Where does this lesson fit in with your curriculum?
As I mentioned before- I am in a STEAM lab and don’t teach a regular curriculum, but I would like to have both the art teacher and grade 4 electricity unit teachers take a look at this.

Which part or parts of the lesson would your students need extra support to be successful? I need a hand lens- some of the kids will as well. They will also need to have a format to pair share or take turns in a larger group. Read and follow directions- be super careful with little led wires.

?? Does polarity matter in this??

If you were to teach this lesson to your class, describe your role during the class. What does a successful teacher actively do during this lesson? I would model each step and then have the kids do it and explain.

If you were to teach this lesson to your class, describe your student’s role during the class. Follow directions, work step by step, write/draw/video into science journal

What does “student success” look like?
excited engaged- able to explain how the code affects color and blink speed.

One more question I could probably google this- but sometimes when I buy multi color leds some are called anode, some are called cathode, sometimes color seems to be affected by the amount of power to the bulb. Not sure how to explain this- is there a simple explanation for elementary.


#34

Yes, when using an “Anode” RGB LED the settings do seem counterintuitive… 0 is full power ON and 255 is OFF. The following turns just the Red LED on:
analogWrite(redPin, 0);
analogWrite(greenPin, 255);
analogWrite(bluePin, 255);

Like you mentioned there are different types of RGB LEDs that are “Cathode” (negative common pin). The difference is the long RGB LED pin called the common pin is negative. This is related to polarity in how these two types of LEDs and their difference in polarity Anode (positive +) versus Cathode (negative -) and how they are wired and controlled in a circuit.
Thanks for great questions!


#35

Where does this lesson fit in with your curriculum (if the lesson is not a fit for the class you teach, how could the lesson be modified so that it is applicable to your curriculum)?
As a K-12 Science Specialist, I don’t have a curriculum that I teach to, but I could see where it would fit in either 4th or 8th grade standards

Which part or parts of the lesson would your students need extra support in order to be successful?
Some may have difficulty seeing where to place the pins on the breadboard (or maybe it’s just me and my old eyes?). A hand lens would help with this or using the magnifier function on iPhone or iPad. Another area of confusion would be the numbers for RBG. It is counter-intuitive for me that a value of 0 is “on” and a value of 255 is “off”. Students with more experience may not have this hurdle, but all students could figure it out with trial and error

If you were to teach this lesson to your class, describe your role during the class. What does a successful teacher actively do during this lesson?
As in the other lesson, I would model it initially and then act as a facilitator, asking questions and encouraging students to persevere.

If you were to teach this lesson to your class, describe your student’s role during the class. What does “student success” look like?
Engagement in the activity, trying new things and being able to explain how the code affects the blinking and the color that is produced.


#36

Question for the Because Learning team:
What happens to the comments/responses to the questions in the lesson? Are they collected somehow and available for the instructor?
If I use this lesson with my students is there a way to see/capture those responses?


#37

I completed this assignment, but I must admit that I had three students doing it with me. At first, I was not able to get everything aligned. The students rewired everything, and gave a lot of great input and advice.


#38

Where does this lesson fit in with your curriculum (if the lesson is not a fit for the class you teach, how could the lesson be modified so that it is applicable to your curriculum)? This lesson fits into our units on coding quite well. It helps explain about colors, as well.

Which part or parts of the lesson would your students need extra support in order to be successful?
My students already helped me greatly by rewiring what I could not see. They loved predicting what the colors and speeds would do.

If you were to teach this lesson to your class, describe your role during the class. What does a successful teacher actively do during this lesson? I would be a facilitator, as usual. A successful teacher guides, but does not do the entire activity for the student.

If you were to teach this lesson to your class, describe your student’s role during the class. What does “student success” look like? In my class, student success is contagious. My students have really enjoyed these projects!!!


#39

Hello. I will not be meeting with my STEAM club members this week, but I just went through this project and I can’t wait to have them go through this activity next week. I love (and they will too) the physical computing aspect. This really opens up “messing” around with the code right away. I thought the creation of the white light was very interesting. I can’t wait to see their reaction next week.

I like doing the lesson first. When I meet with them, I will just give them the kit and the directions and let them go. I won’t let them struggle too much because this is so new to them, but my goal is for them to not only be able to do it themselves, but to be able to guide other students in the activities.


#40

So glad you enjoyed. It’s fun to see the R+G+B turn to white. Excited to hear how it goes with your club. Thanks for sharing.