The introduction was prepared by Lars and Ella. It was very exciting to see all the exchange students for the first time. I was a little bit nervous about  talking  in front of 40 pupils. We explained what  the week would be about and what we would do, and that our scientific  theme for the week would be water. So we started by mentioning some  general facts about water. For example, we said  that we have on Earth two kinds of water, salt and sweet water. Also we have pro’s and con’s about water and  it’s very important and necessary for  human life on Earth. Actually, it went very well, everybody understood what we were saying. The foreigners found it interesting. It wasn’t too long or  too short, it was just perfect.
Flora Chabloz & Ella Van Eynde

On Monday, after the break, we were introduced to Belgian identity. J. Vandewyngaerde, a special and funny man, gave us some information about Belgian trappists because that's one of the most famous things in Belgium and one of his favourite hobbies. We didn't know that there were so many kinds of beer, so it was very interesting. He told us which beers he likes and which  he doesn't like. For example: Chimay, Westmalle, Westvleteren ... After the presentation of the beers, he showed us the typical cheeses of Belgium (often related to the breweries) and everybody could taste them. Everybody in the different groups, Belgian, Spanish and French students, liked 'Oud Brugge' most of all. The 'Chimay' was the worst thing we ever ate. Now we know that tastes are not very different all over the world. Because of this presentation, everybody wants to buy special beers and special cheeses. When we are in Brugge, we will buy a lot of 'Oud Brugge'.  It was a funny and enriching experience for us!

On February the sixth, 2012 the first day of our exchange began. After a short introduction, we took a guided tour through the school. The tour was led by Elise, Michelle, Willem and Edward. After the tour of 2 hours, perhaps a little less, the reactions were very positive: the foreigners thought we have a very large school, which is very different compared with their schools in Lyon and Madrid. During a short interview with Théotim Delannay, he said: “De Bron is a great school, with a very special history. It’s also very fascinating, not every school has its own garden with a pond. Also the food was very good. Another positive point is that temperatures are better in this building.” Another pupil, Marta Rodriguez Ferrero told us: “This school is very different from ours back in Madrid. It’s very big, higher than my school and the building is also very beautiful. It’s also strange for us to see a school with a restaurant. We don’t have a midday meal at our school. When school finishes at 2 o’clock, we go to eat something in town or at home.”  
We started our tour in the restaurant. We briefly explained to them some general rules about our school (no chewing gum, no phones, ...) and how they could get a meal in the restaurant. Then we split into two groups and each took his own route. It brought us along the most famous spots in our school. Also the most special ones: the remaining pieces of our chapel, the Van Biervliet room and the basement. We were also lucky that we could visit a few lessons: physical education, where the pupils were very kind and showed us one of their best dances. We continued our tour along some other, less known places: the Harry Potter stairs, the computer class, the lunch bar and the art hall in the basement. Maybe a guided tour isn’t always that interesting, but I think we were able to show them how pretty our school can be.

Lara from Madrid:
The first thing I thought was that it would be very cold but it was very nice, and what surprised me was that the people are very polite in Tielt and in Belgium in general. The Spanish people were very nervous but I was calm because I like this type of game. The gameconsisted in finding the hidden clues inTielt buildings, and so we did a small tour of such a welcoming city. What I liked most was the visit to the chapel, because of the older ladies and men who were funny and of course  because of the small but beautiful chapel. I also liked the task in the library because it was great to look for a book in a foreign language and also because it was warm in the library. As a conclusion I want to say that everyone really enjoyed this activity, even though we were a little tired, and we'll never forget this experience and we have new friends now. 
Timothée  from Lyon:
My first impression was that Tielt is a nice city, a bit cold, but with a lot of monuments. People are very kind in Tielt. If we ask them a question, they will answer  with pleasure. For example, in the chapel of Tielt, we met two very kind and funny women! They told us a legend about a Spanish noble man, we had fun with them! There are a lot of things to visit, as the library, the chapel. I think that Tielt is a city with a lot of historical facts and stories.To visit Tielt, we did a game. We had to find certain places in Tielt like a chapel, a church, a library; and some students were at some of those places and to find the next place to go to, we had to fulfill a task, such as take a funny picture with a tank, find a book in a library and tell the story to a student etc... When we finished, we had a break, and we went to at a café to have a drink and if we wanted, we could buy things for our families etc... At 5 o'clock we had a reception in Mulle de Terschueren: there we met an assistant of the mayor, who made a speech. We also met journalists, who took a picture of us for a newspaper. Our  partners are very kind, and the Spanish people too! It is a good experience to do this trip with them!

Tuesday, we went to the wastewater treatment plant 'Aquafin' in Harelbeke. We had a very special guide, named Lodewijk Janssens. He was born in Africa, and now lives at the seaside. He told us a little about himself. Once, he crossed the Channel, he swam all the way from France to England in 20 hours! Mr. Janssens gave us an explanation about the wastewater treatment.  We liked this part because it was very interesting and we were inside, so we didn't have cold. The guide explained us the wastewater treatment in a practical and simple way. Actually, it was quite funny,  so we had a nice time. Then we did a tour trough the wastewater treatment plant and saw every step the treatment takes. Everyone was amazed by the enormous size of the installation. At some places, there was a strange smell, caused by the huge quantity of waste.  But it was very cold so it was difficult to pay attention the whole time. Even though it was very cold, we can say that it was an interesting experience. We learned a lot about the wastewater treatment and the importance of it. And hopefully, we are now more conscious about our water use, and we will do our best to preserve our precious water. 

At 5h30 we arrived at the Terminus in Tielt to eat some real Belgian fries. We had made a reservation for something about 50 people. Celeste, a student from Tielt, had already asked all the pupils what they wanted to eat and drink and then she sent the list to the Terminus. We all sat on a huge, long table and 20 minutes later they came with lots of food. Then the food was divided to all the students with the help of the teachers. Then everyone ate their food with a smile. Thirty minutes later, we all left the restaurant and went to a bus station, just next to it. We took a bus all together in order to go to Pittem. Next to a student’s house in Pittem, there was a bowling center. The group was divided in 7 groups of about 8 people for two magnificent games of bowling. We also played some others games: four-in-a-row, billiards, football table. At 10 o’clock, everyone went back home. That’s how a super evening in Belgium ended.
Andreas Ballekens and Elian Zhang

At 8:30, we took the bus to visit HOWEST in Kortrijk. At first, we listened to the speech of a teacher who worked there. We found that the speech was too complicated to understand it. After the speech, we split into two groups to visit the school and we did some experiments. In the first experiment, we had 4 glasses of waste water, and we measured the pH of each one. Then, we added some products to remove heavy metals. In the second and third experiments, we measured the presence of some factors like phosphates, nitrites, nitrates and the ammonium concentration. We calculated the PI of water based on the results of the experiment. It was a long and interesting day. 

On Thursday we went to the Industrial Tufting Company in Tielt. We had a tour that lasted for about two hours. During the tour we saw the process of how they made
their carpets. We had to wear fluorescent jackets for safety reasons because there are a lot of dangerous vehicles driving around in the factory. The theme of the exchange project is water so we also saw how they cleaned their water over there.

After we visited Aquafin and HOWEST, we did something totally different. We went to the Rodenbach brewery. Rodenbach is a redbrown beer, brewed in Roeselare since 1821. It’s a unique beer, known all over the world. It’s also the most refreshing beer of the world, but it wasn’t necessary because it was minus 10 degrees outside. First, we  got an introduction about the wealthy family of Rodenbach, they also explained us how the brewery grew over the years. We saw a short film. Then they divided in two groups, and we started our tour through every section of the brewery.
The guide told us how they make beer from a basic product. Typical for Rodenbach is their unique brewing-process. There are two yeast-phases: in the first phase, the high yeasts come together with the lactic acid-flora. After that the fermentation goes on in oak barrels. It stays there for two years, and then it’s ready for consummation. Then, the tasting-part started. We were allowed to taste two types of beer: the normal Rodenbach and the Rodenbach Grand-cru. They both were pretty good, but for the most of us, the first one was better.

On Wednesday we went to Ghent. Early in the morning we took the train and the tram and finally we arrived at the Gravensteen. there our day started. Martha and Liesbet gave us an interesting explanation about the history of the castle. Leonie, Martha, Liesbet and Astrid had prepared a game through the city. The first step of the game was to find a tourist who would fight for one group like a real knight of the Gravensteen. The only problem was: there were no tourists in Ghent at 9.30 in the morning. So the
students of Lyon and Madrid fought for themselves. The best fighters could leave first. They got photos of all kinds of things they had to find on their way: 't dreupelkot, monuments, a famous door, ... When they found a photo, they had to take a photo of it with the group. There we had a second problem: there was a very nice guy, who also was a guide, who wanted to take one of our groups on a trip. Of course they joined him, and so they got lost. Fortunately for us, there still is something like ' the phone'. When all the groups had finally arrived, after a long walk in the cold winter of Belgium ( MUCHO FRIO!!!), we could go inside the NT Ghent to answer some questions about Ghent and what they had seen. To answer these questions, they had to search in the cathedral of Sint-Baafs, and on the square "de botermarkt". The winning group could enjoy one of Belgiums specialties: chocolate. After everyone was warmed up, we could go and discover the well known shoppingstreet "the Veldstraat" in Ghent. Here the foreign students spent all their money on souvenirs for their families and friends.

We went to Ghent to the bio-engineering faculty. When we arrived we could take a seat in a large auditorium. Professor Boone gave us an introduction to new sources of energy. After listening to his interesting speech , we did a tour around the university. Four guides took four groups to a different room. There we got a fifteen-minutes explanation by students about their experiments and work. They were both proud and enthusiastic. The explanation in the auditorium took half an hour. Some students had problems with understanding because the professor used difficult scientific terms. Other students were a bit tired and dozed off but most of the students were interested. After the introduction we were divided in small groups. That was very good because then we could ask questions if we didn't understand. We actually saw that scientist are busy with ecological engineering. We think that in future we will need this a lot and some of us might even want to become a bio-engineer. In future the world' s resources will get depleted and in that case it could be useful to have such scientist to find a solution. It was surprising that they use bacteria in a good way. We used to think all bacteria are bad for us, but  actually not all bacteria are harmful! We even need good bacteria to survive! Another advantage was that we didn't have to stay outside because it was very cold. The Spanish and French felt like home because in some rooms it was like 38 degrees! :-) 

On Thursday morning we had a practicum at school about the light microscopic structure of cells. We looked at the structures of waterweed, starch of potatoes, starch of maize and onion. First Emmely, Sara, Martha and Liam gave some information about those organisms.
1) Waterweed is used in ponds to increase the oxygen because it is responsible for photosynthesis. It is also used as food for animals. 
2) Green algae live in oceans and seas. They contain the same type of chlorophyll, pigments, starch and cell membranes of cellulose as plants. Most chlorophyts live in sweet water, but there are also species that we can find in salt water, like plankton. They also do at photosynthesis that means that they absorb carbon dioxide and water that they transform into sugar and oxygen. Because of the sugar they are able to grow. Some water animals can be fed with green algae. The oxygen that they produce is
used for breathing. In this way life was created. 
3) Starch is a carbohydrate constructed from a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all the green plants as an energy store. It is the most common carbohydrate in the human diet. It occurs in large quantities in staple foods for example potatoes, wheat, maize (corn), rice,…
For this experiment we’ll use the starch of potatoes. 
4) Onions have a strong flavor and scent. In general they have a papery exterior sheet over a layered core. Onions are used all over the world in the kitchen and they exist in all kinds of shapes and colors. We explained how they have to work with the microscope.
Step 1: use a clean glass and apply one drop of water.
Step 2: apply a small amount of cells from the waterweed to the water and make sure you don’t use to much cells. When you do the next experiments with the starch and
the onion, you have to use very little amount of starch. And for the onions you have to pull a small piece of tissue.
Step 3: put a coverslip on the specimen, try to avoid air bubbles.
Step 4: take away excess water with absorbent paper.
Step 5: now you have to twist your preparation all the way to the top and observe it with the smallest zooming first, and if you can’t see anything you go to a bigger zooming. Make sure you only use the red and the yellow ones. 
Step 6: sketch some cells on the paper you received.
Step 7: compare the size of the studied cells.
We also did some research on glucose in Coca Cola Light, normal Coca Cola and Fanta. Glucose is important because it gives us energy. It is actually produced by plants who do photosynthesis. We determined the amount of glucose with Clinistix and when the stick turns purple, it means that there's a lot of glucose. When we put the Clinistix in the Coca Cola, the Clinistix turned purple. In the Coca Cola Light the color of the Clinistix didn't change, it stayed pink. And in Fanta the clinistix changed a little bit, it also became purple, but the color was not as dark as in the Coca Cola.
Our last experiment was a comparison of the proteins in water and in milk. Proteins are very important because you need them to grow and they are essential for organisms. We can look for proteins with Albustix. Normally the color of the Albustix is yellow but when the albustix gets dark green it means there are a lot of proteins. When we put the Albustix in water, the color didn't change. When we put the Albustix in milk, the color got dark green.
My opinion on this project is that it was a unique experience and above all because I love biology. I loved using different types of equipment and learning new things, especially because we don't get that occasion very often in our school in Madrid.

On Thursday we did some experiments about the purification of water. We discovered several separation techniques to divide two substances. A Belgian told us that there are three separation techniques to separate heterogeneous mixtures. These techniques are called decanting, filtration and centrifugation. To separate homogeneous mixtures there are a lot more separation techniques: crystallization, distillation, adsorption, extraction and chromatography. After the introduction about the different separation techniques, we had to think which technique we could use to separate the different mixtures that we could find on our table. To separate these substances we used a lot of substances that we didn’t know yet. Now we know that we can use activated carbon to get a red colour out of water. Everybody worked really good. We all felt like real scientists when we were doing the experiments because we had to put a white coat and glasses on. Fortunately, there were no accidents except some little problems like some people burned their fingers a little bit. There was also a little problem with the Bunsen-burners because some people were scared of the fire. But the main conclusion is that it was fun and educational. 

Everyone was looking forward to the dessert buffet on Thursday evening. All the mothers were nervous about the reaction to their dessert. When we arrived at the school restaurant, it almost seemed like a top restaurant. The tables were decorated with some greenery and the buffet was beautifully presented. You could choose between a lot of different desserts, thanks to the list we had to make before.  You could take a piece of cake or a plate of tiramisu, and also the chocolate mousse and pudding were popular. Everyone liked the desserts very much. The pupils invited their parents to the buffet, and some people even went a second time. We think they forgot that they had to dance immediately after that. But in this way we could burn all the extra  calories.  
We started the dance evening with the Polka, with which we had a great time while the professional dancers took us all around the dance floor, and we ended with dances that were both fun and difficult which made us all have a reason to keep dancing. At first, we thought that it was going to be a boring evening, but by the time we started eating the desserts we realized that the fun was just about to start. It was amazing that everybody wanted to dance, even the oldest and the youngest ones. The names of the steps were very strange, but once we saw how to dance them, we thought: why not give it a try? It is nice to see that in these days, those types of dances are still alive and everybody can dance them, no matter where you come  from, how old you are or whatever  problems you may have, because dancing can make you forget all the worst things.