Bernard Nebel
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This sounds fine. Plus, you illustrate an important aspect of learning. When you can take a concept and explain it your own words, it shows you have really mastered it. Nice work. However, I would make an adjustment to your line, ” The sensation of weightlessness does not mean you dont weigh anything at all.” This is where we should switch from speaking of weight to speaking of mass. That is, a scale will read different weights depending on gravity–zero in a state of free fall. But you and anything else remains constant. We speak of that “weight” that remains constant as mass and measure it in kilograms. That is, a mass of 10 kilograms will remain 10 kilograms regardless of any force of gravity including zero force.
Thank you for your question. Please ask further.
There is nothing like experimental data to get at the truth.
You have discovered an error in the text. The baking soda-vinegar reaction is endergonic. That is, heat from the environment is sufficient to drive the reaction. As heat from the environment goes into the reaction, the temperature falls.
Congratulations and thank you for exposing this error in the text.Sorry to harp on what you already know well, Cindy. I try to compose answers that speak to others in the group. I hope more will join in and comment or ask questions. I would love to see this group generate more questions and discussion.
Regarding your first question, everything human-made starts with from something biological (add) or NATURAL EARTH categories (or both). A tin can, for example is from natural earth materials–iron ore. (How much work sheet stuff you have your son do is up to you. If he enjoys it, fine; If he doesn’t like it, go easy on it. We don’t want him to get the feeling that science is too much forced dull work.
To round out the concept, introduce the word “resources”. Everything human-made demands starting with certain resources–biological and or natural earth.
Regarding your second question. I would let it go for the time being and move on to Lesson C-1. There you will develop concepts of energy and forms of energy, which are very different from any form of matter. Then you can come back to fire and the sun. What we witness here is heat and light, i.e., forms of energy.
The concept you are heading toward is that we have two things: matter (biological and natural earth) and energy, which makes everything go, work, or change. Energy becomes a required resource for everything we do/make in addition to the material resources.
Please don’t expect that learning should occur in specific steps that kids can check off on a worksheet. The vastness of everything out there is bound to cause confusion and missunderstandings. The real learning occurs as you recognize and accept the confusion and struggle with sorting it out and correcting the misunderstandings. You are on the right track by asking questions. Please keep at it.
Thank you for your question. I think your son (for age almost 5) is expressing remarkably good knowledge and understanding. A perfectly logical argument can be made for paper being biological as it is made from from trees. It is quite arbitrary that we move it into the human-made category to express the role that humans played in producing it. Recognizing that everything human-made starts with resources from biological and/or natural earth categories should be a major point of this lesson.
I don’t know if this helps. Please ask further as you like.
Thank you for your question. I think your son (for age almost 5) is expressing remarkably good knowledge and understanding. A perfectly logical argument can be made for paper being biological as it is made from from trees. It is quite arbitrary that we move it into the human-made category to express the role that humans played in producing it. Recognizing that everything human-made starts with resources from biological and/or natural earth categories should be a major point of this lesson.
I don’t know if this helps. Please ask further as you like.
Hello Sherrie,
Kids should have plenty of experience with pocket magnifiers before proceeding to a microscope. Then, the general type of microscope you want is shown here:You may wish to go up from here and get a mechanical stage and diaphragm condenser for better control of light, and other features as you may desire. Of course you will need slides, coverglasses, etc.
Please ask further questions as you wish.
The Brock microscope is the one microscope that I DO NOT recommend. Focusing is very tricky. Then, when you wish to go from scanning to higher power you must disassemble, screw in the higher power lens, and refocus. Refocusing under the higher power is almost impossible.
Therefore, go with the three-lens, par focal, standard student scope, an example of which may be seen at
They are actually less expensive than the Brock.
That’s a good question. I’ve had to think about it too. In answer, I changed the question to, “What do you need to feel gravity, i.e., have a feeling of weight?” My reasoning: You need to be on a platform (something to stand or sit on) that is holding its position within a gravitational field. An airplane is holding its up/down position within the earth’s gravitational field, forward motion notwithstanding. Therefore, aboard the airplane you experience gravity much as you do on earth. Either that or you must be accelerating or decelerating so you feel the inertial force, which is indistinguishable from gravity.
Now, assume you have blasted off on a straight line mission to Mars. After gaining required speed, engines have been turned off; hence, you are neither accelerating nor decelerating so you feel no force from that. Nor is your rocket ship holding a position within a gravitational field. It may be traveling at great speed in a straight line, but it is not moving or holding a position counter to any gravitational field. Therefore, despite its straight line of travel, it and you in it are in a state of free fall within whatever gravitational field(s) are present. Therefore, you would feel weightless. Please ask further or give an alternative argument.
The following video, which shows diagrams, provides an excellent demonstration of how latitude is determined from the North Star:
Knowing that the sun, at the spring and fall equinox and at high noon (the sun at its zenith) will be 90 degrees exactly above the equator, you can do the same thing with reference to the sun. Of course, in this case, you have to subtract your measured angle from 90 degrees because the equator is designated as zero degrees latitude. By making proper adjustments, this process can be used for determining latitude at other times of the year and the day. Mariners had and still have tables for making those adjustments.
The following video may be helpful. (Thank you for you question. I hope this answers it, but please ask further.)The following video, which shows diagrams, provides an excellent demonstration of how latitude is determined from the North Star:
Knowing that the sun, at the spring and fall equinox and at high noon (the sun at its zenith) will be 90 degrees exactly above the equator, you can do the same thing with reference to the sun. Of course, in this case, you have to subtract your measured angle from 90 degrees because the equator is designated as zero degrees latitude. By making proper adjustments, this process can be used for determining latitude at other times of the year and the day. Mariners had and still have tables for making those adjustments.
The following video may be helpful. (Thank you for you question. I hope this answers it, but please ask further.)“My children tend to forget…” Your children are not unique in this, nor is it just children. We all forget things that are not brought back and refreshed now and again. Call it review, but that review does not need to be from a book. In fact there is a better way.
The whole objective of science is not to learn a bunch of facts; it is to become able to look at the real world, both natural and human-made aspects, and gain understanding as to why things are as they are and happen the way they happen. For example, suppose kids have learned about inertia (Lesson C-5). The best way to review this is not to read about it again in a book; it is to call it mind in real life situations. Why is important to fasten your seat belt? What is involved in kicking mud from your boots? … a dog shaking water from its fur?
In short, I believe the best sort of review is bring kids to consider things/happenings in the real world and with Q and A bring them to consider the “what” and “why” in terms of their learning (or perhaps formulation of questions for future learning). For ideas in doing this, see the sections in each lesson: “Questions/Discussion/Activities to Review, Reinforce, and Assess Learning” and “To Parents and Others Providing Support”.
I hope others will respond here as well.
Best, Bernie Nebel
