About the tournament

The tournament is composed of four selective Science Fights (SF), one Semi-Final SF, and the Finals. Throughout four selective SFs, each Team meets other contestants, and no Team is eliminated. These competition rounds are played in parallel all-play-all Groups. The Teams are rotated after each SF to ensure as far as possible that no two Teams meet more than once. Selective SF1 and SF2 are focused on main IYNT problems known to the Teams in advance. Selective SF3 is focused on problems Invent Yourself with the original problem statements by each Team. Selective SF4 is focused on additional problems that the Teams are given immediately before the Fight to solve during a 45' preparation phase.

Overview of a Science Fight

Discussion of the IYNT problems during our events has a form of scientific discussions called Science Fights or SF, shortly. A Science Fight resembles a scientific seminar or a graduate thesis defense. In a Science Fight, the Teams switch their roles and take to the floor as Reporters, Opponents, and Reviewers. Their performance is then graded by professional jury of research scientists and educators.

Roles In A Fight


Three Teams of six members each are seated in a Fight Room before a panel of jurors.
The Team of Opponents challenges the Team of Reporters on one of the IYNT problems.
If the challenge is accepted by the Reporters, one Team member takes to the floor and presents their solution in an 8 minutes talk.

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The Team of Opponents poses clarifying questions to the Reporter and briefly prepares.
A Team member of the Opposing Team takes the stage, criticizes the Report, and draws attention to possible shortcomings and errors in the understanding of the problem and in the solution.
This leads to a discussion between the Reporter and the Opponent in which the Reporter defends their results.

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The Team of Reviewers assesses the outcome of the debate and draws impartial conclusions.

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The Jurors hold up their scores and the Chairperson concludes the first Stage which lasts around 50 minutes.
After a short break, second and third Stages continue, and all Teams switch their roles.

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The problems for the 9th IYNT 2021 are presented below. You can also download them here in pdf format.

Main Problems for Science Fight 1
1. Coin in a balloon. An inflated air balloon contains a coin and is gently moved to set the coin rolling around the inside of the balloon. Explain and investigate the buzzing sound produced in this experiment.
2. Liquid layers. Water and vegetable oil do not mix and form two layers in a beaker. It is possible to fill the beaker with many more layers of immiscible fluids. How many layers can you obtain? Investigate the motion of the interfaces if the beaker is disturbed or shaken.
3. The Purkinje shift. As light levels decrease, human eyes perceive relative brightness and contrast of various colors differently. Perform experiments in controlled conditions to investigate this effect.
4. Making butter. Investigate the methods to produce homemade butter from milk or cream. Investigate how properties of the butter depend on relevant parameters.
5. Lake water. A drop of water from a natural pond may contain bacteria, archaea, algae, fungi, protozoa, and other organisms. Perform observations to identify as many species of living organisms as possible. What are the chances that another drop contains a different selection of species?
6. Tall towers. A tower is built by stacking rectangular bricks on top of each other. Some people argue that the maximum height of the tower is limited by the human skill to place the bricks gently; others may say that the limiting factor is non-perfect shape of the bricks. Perform experiments to outline the factors that limit the maximum height of such a tower.

Main Problems for Science Fight 2
7. Electricity meters. Energy meters installed at your home have been measuring power usage for decades. Collect periodic readings for a sufficiently long period of time, e.g. last 20 years, and identify subtle or significant changes in energy using behavior at your home. When did your family switch from incandescent to fluorescent or LED bulbs? Is there a history of electric heating or air conditioning? Are there regular seasonal variations in power usage?
8. When dumplings rise. Frozen dumplings sink in water. However, they rise to the surface when cooked in boiling water. Are the dumplings ready once they float? Investigate this effect.
9. Salt and ice. Study the effectiveness of salt to melt ice cubes.
10. Blurred text. Printed text is well visible if covered with a piece of transparent film. As the film is lifted, the text becomes blurred and may gradually disappear. What parameters of the film are relevant? Investigate this phenomenon.
11. Oxygen from plants. Suggest an experimental method to measure how much oxygen is produced by a green plant.
12. Zinc layers. If a copper coin and small granules of zinc are immersed into a solution of zinc sulphate and then heated, a layer of zinc appears on the coin. What is the thickness of the zinc layer? What other metals can be covered with zinc in such an experiment? Investigate and explain the effect.

Problems Invent Yourself for Science Fight 3
13. Invent Yourself: Skin conductance. Conductance of human skin is often dependent on psychological condition and emotional stimulation. Suggest an interesting problem requiring experimental measurements of respective parameters.
14. Invent Yourself: Epidemiology. The human society has been profoundly affected by the COVID-19 pandemic. Propose a study involving analysis of available epidemiological data for the pandemic.
15. Invent Yourself: Hearing range. There is a considerable variation in the range of frequencies that can be heard by humans and other mammals. Suggest a problem to investigate the lowest and highest audible frequencies for specific species of societal groups.
16. Invent Yourself: Weak signals. Controlling signal-to-noise ratio is important in many measurements to distinguish a meaningful signal from statistical fluke. Propose a problem requiring experiments to detect very weak signals.
17. Invent Yourself: Standing waves. Formulate a problem about an interesting experiment where standing waves are observed.

Get Involved

If you are interested in participating, please fill the form and we will contact you.

Registration begins in August of each year after the problems are published. Students all over Greece can register and start working on the problems.
It is not necessary that a team consists of students from the same school.
Students must be at the proper age, from 12 to 18 years old (High school students), both from private and public schools.
Hellenic Physical Society (EEF) is responsible for organizing the students in teams and help them through the problems.
Students of a different nationality that study in schools (private or public) in Greece have also the right to participate.

Latest News


8th IYNT 2021

  • 8th IYNT will take plase in St. Petersburg (online).
  • 15 teams are perticipating, including 4 Greek teams!
  • Good luck to all Greek teams,
    Anatolia, Fryganiotis, Pinewood, Raptou!

8th IYNT Results

  • 3 Bronze Medals for Greek Teams!
  • team Fryganiotis
  • team Anatolia College
  • team Pinewood

Ο διεθνής διαγωνισμός 8th IYNT (International Young Naturalists Tournament) πραγματοποιήθηκε διαδικτυακά με διοργανώτρια πόλη την Αγία Πετρούπολη της Ρωσίας. Η Ελλάδα συμμετείχε με 4 ομάδες:
Anatolia College: Zoi Maria Petridou (captain), Nikolas Papageorgiou, Eleanna Papaioannou, Aggelos Skiadas, Alexandra Thereianou, Alexandros Kiziridis (leader)
Fryganiotis: Menelaos Raptis (captain), Evelina Gialama, Christina Farmaki, Myrto Floridou, Nafsika Koutava, Myrto Terpsiadou, Evi Parisopoulou (leader)
Pinewood: Kelly Hu (captain), Anna Arsenou, Christos Kalemkeris, Alisa Otchertsova, Pavlos Paraschoudis, Maria Karaveli (leader), Clare Squires (leader)
Raptou: Christos Michos (captain), Eleftheria Nikolaou, Konstantinos Gkanatsios, Thanos Tzikas, Apostolos Nikolaou (leader), Vasileios Gkanatsios (leader)
Για τη συμμετοχή τους στον πληρέστερο διαγωνισμό Φυσικών Επιστημών, οι ομάδες ετοίμασαν επιμελώς τις λύσεις τους σε 17 ρεαλιστικά προβλήματα (real world problems), οι οποίες αποτελούν μία επιστημονική προσέγγιση πάνω σε αυτά.
Στον διαγωνισμό παρουσιάζουν τις λύσεις τους και τις υπερασπίζονται έναντι των άλλων ομάδων, στα λεγόμενα Science Fights. Είναι κατανοητό ότι απαιτούνται πολλές δεξιότητες από τους μαθητές και καλή προετοιμασία.
Οι ελληνικές ομάδες, υπό την καθοδήγηση της Ένωσης Ελλήνων Φυσικών και του εκπροσώπου της, κ. Απόστολο Μιχαλούδη, κατάφεραν να έχουν μία αξιέπαινη συμμετοχή. Μάλιστα, οι ομάδες Anatolia, Fryganiotis και Pinewood κατέκτησαν χάλκινο μετάλλιο! Συγχαρητήρια στις ομάδες, αλλά και στους καθηγητές τους και τα σχολεία για την υποστήριξη!

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