When Is Late Too Late

The Question:

Once you observed an ecological change in your neighborhood which reaches a tipping point – how would you identify the change and give solutions?

Blossom Video link:

When Late is Too Late


  1. To be aware of the dramatic changes in your area and study the problems that may occur
  2. Define the tipping point.
  3. Build or combine few materials into a kit which will be used to test the issue.
  4. Decide which are the important parameters, make an experiment and check these parameters.
  5. Analyze the results of your experiment and find the value of the 
  6. tipping point.
  7. Give ideas of how to improve situation in this case and other cases.



Check your tipping point - did you find the important parameter that causes the dramatic changes?

Check your experiment kit - does it inquire the important parameters that influence the dramatic changes?

Send us your Tippining Point and your great ideas

Provide an answer by clicking on "Map" and then on "Add an Answer".

Results, Analysis and Discussion

1.  varsano merav (15.08.2017 pm 08.43.24)
Peer Assessment by Merav Varsano

Great Job !!!

The assignment is very clear and simple.

You described the consept 'Tipping Point' in a very good way in the three diferent vidios.

There's a lot of creativity in all the videos, but I think that the 2 vidios that demonstrate the tipping point are very similar.

The project raises an important issue from daily life: water pollution by the industry.

Nevertheless, the video that explains the steps to inquire the subject is too detailed for my opinion and leaves no space for free imagination. I also sugest you to add more questions that will lead the student finding their own problem.





2.  Shalev Smadar (16.08.2017 pm 12.04.30)
Thank you for your comment and compliments

Dear Merav,

Thank you for your comment and compliments.

The two small videos that shows an experiments - showing going one way - and then the other way back - they are completing each other.

The video that explains the steps was made in purpose - very detailed in order to show one fully explained example for the student.

I accept your suggestion of adding more questions that will leads the students to find their own problem - and already implement it.

3.  Zhu Qishuai (16.08.2017 pm 11.08.04)
Peer Assessment by Qishuai Zhu

Well down!

You described the concept of tipping point in a very easy-to-understand way by two short videos.

You did a very significative job, but the two videos can only demonstrate the concept of tipping point qualitatively, we can’t get the current value of the concentration of the water that can make the grape float on the water.

The idea to demonstrate the concept of tipping point is creative and relevant for everyday life, the answer is based on the course contents.

There are some phenomenons which can demonstrate the concept of tipping point such as the water can freeze under zero centigrade, and you can find much more interesting phenomenons in daily life which can demonstrate the concept.

I think if you can demonstrate the tipping concept in a quantitative way, it will be better.

4.  Zhuang Xuan (16.08.2017 pm 11.17.34)
peer assessment by Xuan Zhuang


You have done a great job! The experiment shows the important parameter that causes the dramatic changes clearly, which is the density of the water.


I think we can make the tipping point more measurable, like the PH value example in the Blossom. It is not difficult to get the density of the water when the grape are in different states, and that will help us to know exactly where the tipping point is.


Also, I suggest that we can start the video from a question or a phenomenon in the daily life, so students will be much more interested about this project.


5.  Shen Yi (16.08.2017 pm 11.45.11)
Peer Assessment by Shen Yi

Hello! It's nice to attend your online class and watch the amazing videos:)

First, I would like to say that your topic "When Is Late Too Late" is really a good one which arouses my interest. Also, your directions are clear, enhancing the students' ability of critical thinking and reasoning. I think it's great to take the example of the polluted Kishon stream in Israel near the Haifa Bay to show the dramatic changes in one's area, which is familiar to the audience and therefore can encourage the audience to be aware of the dramatic changes in their lives. And then the definition of the tipping point is explicitly given. I would like to suggest you that it may be better to put this example in the first part of the text as an introduction to the question below.

Also I have a doubt whether the stirring of the chopsticks and the pouring of water in the two video experiments have some interference to the result. And the amount of salt or water added each time may be a little bit too large, which will influence the accuracy of the tipping point.

In general, it's undoubtedly an excellent job. Thanks again for your wonderful videos!

6.  Yuan Shiran (17.08.2017 am 11.13.19)
Peer Assessments by Yuan Shiran

It is not hard to find that your video was arranged logically and clearly, I like it! Your PBL project illustrated how to distinguish problems according to changes happened in out daily life, and then by defining tipping point and showing how it works dealing with the problems.

However, I think you can make improvement in somewhere. Firstly, I think your video is a little bit dense, and almost covered everything that you would like students to learn. I think it would limit students’ performance, there is no enough space to allow them to do critical thinking. Meanwhile, this video it a short one but with too many information, so the illustration sometimes is not very clear. For example, in the graph which shows how PH changes with the distance increasing along Haifa Bay, you illustrated it, but rather in a rough way, so it is a little bit complicated for students to understand. Secondly, the two experiments are good examples, but I think they are quite similar with each other, and the time for each is a little bit long while lacking of interesting things, it’s really easy to get your students bored. Last but not least, why not ask more creative questions instead of doing illustration? I think question-and-answer way can get students involved more in your project, increasing the intercommunication, and help them think and learn better.

History of edits
Edited BY: Smadar Shalev Edit Date: 2017-08-16 09:10:54
Edited BY: Smadar Shalev Edit Date: 2017-08-15 19:38:13
Edited BY: Smadar Shalev Edit Date: 2017-08-15 19:37:20
Edited BY: Smadar Shalev Edit Date: 2017-08-15 18:30:25
Edited BY: Smadar Shalev Edit Date: 2017-08-12 23:17:31
Edited BY: Smadar Shalev Edit Date: 2017-08-12 23:13:04
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