ENERHACK WORKSHOPS

With the water mill and windmill, children can choose whether they want to build a water mill or a windmill and how they want to do it. We had some samples and pictures with us, and everyone could try their preferred way of building. Some even tried their own designs, and the instructors could give advice on how to make the blades more aerodynamic or how to make the most of hydro energy. Everyone who wanted to could also try how much electricity their windmill or water mill produces.

Together with children, we make a lava lamp. The lava lamp itself is based on the reaction of baking soda and acid (such as citric acid or vinegar), where carbon dioxide is released from the composition of baking soda (NaHCO₃) during the reaction. When the reaction is allowed to occur in a non-water-soluble environment, such as oil, carbon dioxide is released in bubbles, which creates the lava lamp effect.

Older children and adults learned about the reaction and why it occurs, while with younger children we talked about what carbon dioxide is. In addition, we talked about why water does not dissolve in oil and what density is.

We make our own cold and hot packs. The experiment itself is simple and doesn't take much time, but it brings a lot of joy to the children when the pack gets cold or hot. We can talk to the children about why some reactions make substances cold and why some make them hot, how energy moves with heat, and what chemical bonds are (with older children).

We will build a hovercraft with children using a CD and a balloon. This activity is suitable even for very young children, and afterwards, we can have a competition to see whose hovercraft can travel the farthest. During the experiment, we can talk with children about pressure and why the hovercraft starts moving. We can also discuss what air and molecules are and why we don't feel the air, but we feel the wind. Additionally, we can build a water pump using the same principles together with the hovercraft.

Together with children, we build a small electric circuit with the goal of powering a small fan (or other rotating device, which the children can make themselves) under our guidance. With older children, it is possible to solder the connections together and teach them how to solder, and with younger children, we can use crocodile cables. Through this activity, children learn about electricity, how electric current moves, and how electric motors work. In addition, we talk about safety.

The difference in salinity creates boundaries between layers of different densities, which makes it difficult for the bodies of water to mix completely.

Based on our experience, we can clearly see this process when we add water with different concentrations of salt and different colored dyes.

This is a fountain that works without a pump! Children have to connect three vessels with straws in the correct order and length, and make them watertight and airtight. Then, when we fill the correct vessels with the right amount of water, the fountain will start working on its own due to gravity and the difference in pressure! It's suitable for both older and younger children, but younger ones may need some help from their parents. The experiment takes some time and care to make everything airtight, but when the fountain starts working, there will be lots of surprise and joy!