How fast does a secret spread

The Power of Exponentials in Daily Life

Watch the Blossoms video called “the power of exponentials”: 


How would you explain the idea of exponentials growth and decay in daily life? Think of creative ideas to model the math concept.


Students can present a picture or a video that shows exponentials in daily life and describe the variables and the equation connected to it. 

Example---How fast does a secret spread 

If it takes a person 1 minute to tell the secret to 2 others (that have not been told the secret before), how long will it take for the secret to be told to 100 persons? 1000 persons? Or even to your country? 

We are looking forward to your ideas!

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

Results, Analysis and Discussion

1.  piorko ran (14.08.2017 pm 08.57.49)
peer assessment

Hi , 

I want to thank you for a very creative video , very nice work . 
The video explains in a very simple way the power of exponential growth .

I think you should have explained in more details the equations that was in the video , it is rather logical , but the video can be watched by students thet do not have the exact knowledge to understand the logic behind the equations .
The video demonstrates the exponential growth by a very familier daily social phenomena - spreading a secret , 

I must comment that the limitation that was in the video - "tell only 2 people " is rather artificial , in real life the secret is spread much faster because people tell more than 2 ....our human curiosity for "forbidden things" makes the motivation to spread the secret very fast....

I reccomend to gain more knowledge on "exponential growth" from economical aspects , there are many articles dealing with the issue as a method for making money  , predicting long term profits , inflation or other ...

Again : thank you for a very clear and simple way to explain the phenomena .


2.  Zhao Minjie (14.08.2017 pm 10.01.47)
Peer assessment for Minjie Zhao




Firstly, I would like to thanks for your efforts. This was an attractive project, the example you gived and the video you made were very excellent, very interesting and sticked closely to your project. On the web page, the titles were outlined in bold letters, it’s very clear and concise and give the students or teachers a quick understand of your project. And for your video example, the backgroud music was beautiful, the exponential was explained clearly enough. It’s really a well-made video.


And in my opinion, with some modification your project will be wonderful. In the first place, in your video from 01:50 to 01:58, the number you showed on the pictures were to small and not very clear, and you left too much blank space in the left. Secondly, I think cooperation is also important in learning, you can consider adding some team workings to teach the students how to cooperate. Also, you can add some peer assessment in your project, the students can assess the model of each other, it will be helpful to critical thinking. At last, please write the names of all the team members on the appropriate place.


Thanks again, you give us a good example to show the creative thinking and the relevance of STEM in our daily lives.


3.  HUANG CHUNXI (14.08.2017 pm 11.36.57)
Peer assessment about the content of the video

Hello Group 7, 

Really great video. You have done the task well. Thank you.

I like the video very much cause it includes the process of calculation and building the model, making it easier for students to understand the question itself and stimulate their creative thinking and critical thinking, after they see the video, they can get a direct cognition of the speed of secret spreading.

In the video, I can get the logic order of the things including it, it's very clear. By using the video, I think that you can educate students in both scientific and mathmatic ways, which is important for their development. Really good example.


I have a question about the content of the original video, there are many valuable things in it, and you choose the question that how fast does a secret spread, maybe there are some limitations in your education process, students can get limited knowledge from your transfering process, why not choose to include more contents and make them connected, and in this way the students can get more things from your video.

And back to your video itself, I think it may be helpful if you don't put the only example but add some other examples related to the topic, even some related simple information, it may help students to find more diversity in the same area, broading their eyes and developinp the creative thinking. In the other side, more than one example means comparable, students can get more useful things and develop critical thinking in this comparison process.

Finally, although there is little research about "How fast does a secret spread", there are still many research about the original topic in other aspects like how to estimate the ROI (Return of Investment) for example. No visions, No missions. This is really important for students to study and research things from different perspectives. This is what us teachers should do.

Thank you again for the really good job!

4.  Deng Lingli (15.08.2017 pm 10.52.04)
Peer assessment by Lingli Deng


It’s a nice shot video. Your video reminds me of “simple is best”. You conveyed the concept of exponential growth very clearly. And you did a good job by combining the live shot with the software demonstration.

I think the video is your advantage, also the disadvantage. Your video attracted all my attention when opening the website. Your word is still a little thin on content. We can’t get logical idea from your text.

And I suggest that you can add a part about how to solving the question you come up with in your video after demonstration of the equations. I think this part could lead student to solve other problems by exponential.

Thanks again for your good job!

5.  FU CHEN (16.08.2017 am 12.18.33)
Peer Assessment by CHEN FU

Hello! At first I want to say I really enjoy your group work.

Actually I was attracted to the cozy and cheerful music from the beginning. A relaxing atmosphere could inspire the study interest and confidence and furthermore, make the class lively!

Second, I think the process you explain the Power of Exponentials is reasonable and clear. Against from the others’ opinion, I do like the secret example (maybe it is because girls always like sharing secrets!). And the tree-figure vividly shows the law of exponential growth.

As far as I think, a mathematical problem could always be divided into three parts: abstraction and transformation from actual problems, model establishment using equations and figures, application into general questions and problems. I think you guys doing a great job in the first two steps, but I think if there are a further consideration and discussion in the last step, the STEM design would be better! The video should give more space to guide students think by themselves.

Last but not least: Math is interesting! I love math! Thank u for ur hard working!

6.  Drobchenko Tania (04.06.2018 pm 06.35.09)
peer review

the question is good in my opinion, it is broad enough to be interesting in many aspects - to track changes in our lives, to identify phenomena, to notice rapid changes in growth or decay, also world population growth is exponential. the presented videos are inspiring and the map is very fun to work with :)

i think that one to the products could also be a code written to visualise exponential growth.

History of edits
Edited BY: Qiling Wu Edit Date: 2017-08-13 20:48:13
Edited BY: Qiling Wu Edit Date: 2017-08-13 20:46:54
Edited BY: Qiling Wu Edit Date: 2017-08-13 20:40:38
Edited BY: Qiling Wu Edit Date: 2017-08-13 20:38:20
Edited BY: Qiling Wu Edit Date: 2017-08-13 20:36:18
Edited BY: Qiling Wu Edit Date: 2017-08-13 20:32:53
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