What to do when a science demonstration does not work?

Despite how much “wow” a successful science demonstration would get, presenters experience double much experience of failure. It is OK if you fail when you are just practicing backstage, but what if you are facing several audience with curious eyes? Here are some tips I conclude from my own teaching and demonstration experience:

Rule 1: Admit it

You never know whether you will fail a second time, so don’t pretend that you “pretended to fail” or declare something like “Ah ha! I did this on purpose” (awkward smile). Just say “Oh I am sorry this failed. Actually, this did not work out several times before as well.”

Admitting your failure will not make your students feel you are “low”, but instead is a good chance to ignite some discussions and thoughts – a perfect time for students to learn the principle behind the science experiment and figure out possible reasons for it to be unsuccessful. Believe me, letting them think on themselves is more powerful than directly telling the influencing factors.

Rule 2: Ask questions

Here is one example from me when doing demonstration on “sharing a coke with salt”. Carbonic acids from coke will nucleate on sharp edges of salt crystals, therefore, it is expected to see vigorous foaming when mixing the two together.

science demonstration

(Thanks to Andrew for the pic. This time the demonstration worked. 🙂

Usually I use Coca Cola, but when I did the experiment with my primary 2 students, I bought Pepsi due to the shortage of Coca Cola in supermarket. It turned out that there was little foaming and even me was a bit disappointed about the results. Having calmed down and I asked the students, “why did we not see lots of bubbles?” They thought over seriously, and gave me a surprise conclusion, “it could be Pepsi having different recipe as Coca Cola, or maybe we leave the can open for too long and the carbon dioxide escaped too much.” Oh my! They are even better scientists than me, aren’t they?

Rule 3:  Carry On

If a science demonstration failed, and you tried several times but could not save it on the spot, leave it. The scene will become more embarrassing if you keep talking to yourself and sweating with no progress. Claim that, “OK I think this is not going to work today…” and redirect your audience, “but, let’s see another exciting one and hopefully it turned out well!” Use your humors to move both yourself and the audience on. But better make sure the next one is really interesting and 99% will work.

These 3 rules are barely some lessons I learned as a young teacher, and I am sure there are ample skills and techniques from your experienced teachers. Please comment below if you would like to share with me, and together become a more effective science demonstrator!

-Alice Yu Yuebo


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s