Playing with water to smell the flag

Learn about water purification, play with marbles to represent planets and program robots. Children can learn about science at the Radboud Kidslab during the four-day walks.

Cotton pads, pebbles or oatmeal: what’s best for purifying water? The children found out on Saturday at Mariënburgplein, where the Radboud Kidslab is located.

In the university tent, a number of Science College employees are preparing to conduct experiments for the youngest scientists.

“The best way to clean water is with a coffee filter,” says Thomas (8). “It has oatmeal in it and there are some stones on top.” Shortly before, environmentalist Katrina Zelin had given him a plastic bottle that he could fill with different materials. He filled it with enthusiasm and poured the murky water into it.

Then he measures the pH of the filtered water with Xylene. It turns out to be about 7.0, which is excellent. “Much better than the first time,” Thomas quickly concludes. “So I can drink it?” he asks hopefully. Xylene starts laughing. No, don’t do that. The pH says nothing about how clean the water is.

floating carts

The interaction between the two is the highlight of the afternoon. Children receive explanations about science in a fun way. In addition to playing with dirty water, they can work with bowling balls and marbles to understand gravity, robots are programmed, floating cars fly back and forth, and devices must be built to escape from the escape room.

By experimenting with the water filter, Zelin hopes to create some awareness — and certainly not just among children. “People flush a lot of water every day, but they don’t think about how much effort it takes to clean it again.”

To reinforce this message, she pulled a jug of water out of the well, where a lot of waste was floating. “See all those plastic particles?” And what about those red threads? They’re pieces of orange or tangerine netting. People open them in the sink, wash their hands and the threads are washed down the drain. But those particles slip through all the filtration systems and eventually end up in the river.

Sun and planets

A little further away, seven-year-old Philip is busy playing ball with his twin sisters, Leah and Livia, both 5. A large black canvas is stretched out in front of him, with a bowling ball in the middle. The canvas is supposed to represent the universe, with the ball in the middle of the sun. The children can roll the marbles across the canvas. Because the bowling ball changes the tension on the canvas, the path of the balls changes as well, or so the explanation goes.

“It’s nice to have knowledge passed on this way.”

The three of them excitedly throw marbles one by one onto the canvas. “Look how fast it spins,” Philip shouts as he jumps for joy.

Although the children are mainly interested in playing with the balls – lots of them bounce off the fabric and that’s fun – they also retain essential information. “This is the solar system,” Philip explains. “And the marbles are the planets that orbit the sun. The sun, that big ball in the middle.

Zillien is pleased with the day and the rest of the visitors. “It’s so nice to see the kids’ curiosity. When I was a little kid, I always enjoyed playing with dirty water, and I still do. It’s great to get science across in this way.

There will be more science experiments for children to do at Mariënburgplein in the coming days. These vary per day. For example, surgery can be practiced on Sunday and Monday, and an exploration trip through the universe is planned for Tuesday. The whole program is It can be found online..