here is how to easily make a baking soda rocket.
-empty pop bottle -hot glue
-vinegar -wine cap
-Baking soda toilet paper
Step 1: Fin
The first step is to draw the fin of the rocket on some cardboard and to cut them
Step 2: Fin-2
Now glue the fin to an empty pop bottle with hot glue. Make sure all the 3 fin are at the same distance
Step 3: Primer
Now it is time to make the primer of the rocket by means of paper and of Baking soda. It is necessary to roll up the powder in the paper and to close every extremity with the brooch. The brooch has to exceed on one side.
Step 4: Primer
The rocket is ready to launch. you just need to put a bit of vinegar in the bottle and set the primer In the mouth of the bottle so that it does not touch the vinegar.Use the cap and the brooch for this like show on the picture.
Step 5: Launch
Now just turn the bottle upside down and the rocket should go off. If not shake it a little bit. Here is a youtube video of my lunch. You can customize your rocket as you want, make it bigger, put more fin, add decoration...