What You Need:

Preparation:

• Square of tissue paper (like what you would use to wrap a gift) which needs to be prepared ahead of time.
• Saltpetre (Potassium Nitrate) – this can be purchase from Amazon.com using the link below:
  • The Science Company, NC-8794, Potassium Nitrate, (Saltpeter), Food Grade, 100g
• A small leak proof container in which to store the solution since it has a long shelf life and you can use it many times over. I used a very small canning jar (about 2 to 3 inches tall).
• Small paintbrush
• Frame to stretch the tissue paper on when it is finished (I made this out of thin scrap strips of wood I had laying around)
• A lighter
• A “punk”… as in the lighters they give out for free at fireworks stands.
  • NOTE: I recently realized that I had forgotten to bring one of these with me and a brilliant man (Bro. Tim Patterson from Hattiesburg, MS) had the great idea of using the “incense” sticks that can be purchase from just about anywhere and they WORKED GREAT!  Thank you Bro. Patterson!

About the Lesson:

We love science experiments but this particular one nearly crosses the line of science and drifts into that of magic.  It is entertaining to audiences of all ages and while it does require some preparation, it is relatively easy to do.

What the audience sees is a blank canvas stretched out on a frame of some kind. When you are ready to begin you light a portion of the tissue paper and a design begins to miraculously etch itself on the canvas.

Lesson:

We used this lesson to illustrate the importance of a young person allowing God to design their life rather than them attempting to do it themselves. We emphasize the point that as a young person you are a blank slate.  You are innocent and clean and life has not yet been able to affect you nearly as much as it might have to an adult.

We have done this lesson where we actually had two canvases, one prepared and one that was just tissue paper. On the one that was not prepared we had two goofballs attempt to design their own canvas because they were not willing to give it over to God. Using paint and sharp implements they proceeded to mess the job up horribly by finger-painting, poking and tearing until even they finally realized what a terrible job they were doing.

The teacher with the prepared canvas will then ask the kids what they would like to be when they grow up. You will get an assortment of responses ranging from firefighter to police officer to astronaut to preacher and everything in between. You explain that it is a great thing in life to have goals and to prepare yourself for the work of the kingdom of God but you always need to allow God to have the freedom to work in your life. At this point, ideally using a punk (the safe lighters that they hand out at fireworks booths) you would light the canvas, preferably at the lowest point you have prepared on the canvas.

The burning time of the design will vary somewhat depending on what you have painted but I typically would outline a simple cross which can take up to two minutes to complete. While this is burning you can continue to engage the kids and compare the differences between the torn and ugly canvas versus one that God designed.  Ask the kids which one they prefer.

As the burning does take some time, you can talk about how God working on your life doesn’t happen overnight… that it takes time, work, prayer, reading your bible, coming to Sunday School and church service and patience but eventually, with God’s help, your life will turn into something amazing.

At this point the design should be nearly finished and as it burns to the top you should be able to pull it off and hold the completed cross and give your final points. It is a very dramatic ending and should be a great clincher to your class.

Preparation:

1. You need a square of tissue paper (like what you would use to wrap a gift) which needs to be prepared ahead of time.
2. You need saltpetre (Potassium Nitrate) which you can order online from a variety of sources (not Amazon unfortunately). I think I purchased a 5 pound bag for approximately $15. You will also need a small leak proof container in which to store the solution since it has a long shelf life and you can use it many times over. I used a very small canning jar (about 2 to 3 inches tall).
3. I filled the jar about three quarters full of water and then began adding small amounts of the saltpetre into it, stirring it in as I did so. I kept adding more and more of the saltpetre until finally it stopped dissolving into the water and there were some grains on the bottom of the jar. At this point, the water was supersaturated which means that the water cannot absorb any more of the saltpetre.
4. You prepare the paper by painting a design on it using the super saturated solution of saltpetre and water. Using a small paintbrush you paint a continuous line on the tissue paper using the saltpetre / water solution. You want the design to be simple because the lines when burned will expand to several times their original width.  We have tried several designs but the one that always seems to work the best is an outline of a cross although I’m sure that many of you will come up with some great ideas as well. Please share them with me as you do.
5. Allow the design to dry completely and when it is finished the design should be nearly invisible. You will then stretch it on a frame of some kind. I built mine out of small strips of wood into a square which matched the dimensions of a typical piece of tissue paper (I think it was a 22 inch square?).  I held the tissue paper to the frame using simple paperclips.
6. Have 2 responsible people hold either side of the canvas frame and make sure all fans and even strong air conditioning is temporarily turned off then you are ready to try it out.
7. You have to be very careful when lighting the design. First, be sure to only light a part of the canvas that has the design you created on it. The tissue itself is very flammable and if you light the wrong thing it can burn up easily ruining the lesson. Once the design is dry it can be difficult to even see the lines on the paper even when you are very close up to it, so I typically make a small mark on the paper showing where I should light. Also, direct flame is not a very good idea although it can be used in a pinch. The best thing to use, as mentioned before, are the small stick lighters that they hand out at fireworks booths. This allows you to apply a coal to the saltpetre without an open flame which mostly eliminates the possibility of lighting the tissue paper on accident.

If all goes well, and you obviously want to PRACTICE THIS AT HOME FIRST, you should see a bit of a sizzle and then the line will begin to eat it’s way around the design you created.  It will burn the quickest on vertical lines and will be pretty slow on the horizontal.  I like the design to be completely closed so when I light the bottom the design will begin in two directions at once and will ideally meet together at the very top.

I hope this helps and that you are able to use it in your classroom!