what country are you in now ?
different countrys have vastly different school systems and higher education systems.
language is also a consideration.
sometimes there are foundation aspects of science that you must learn while you think about the more complex issues.
13 years old is a very emotional stage. many of your peers are more concerned with social networking and learning how to interact, control and manipulate social groups and processes.
thats normal.
greece has a terrible financial situation currently, so the schools ability to deliver higher education(school for advanced students and school for students with learning disabilities) has probably been taken away by money being cut to the school.
they probably dont have enough money to pay for the basic stuff as it is.
good science teachers are extremely rare.
you will be VERY lucky to get 1 good science teacher per school.
this means you must motivate yourself to find ways to help yourself.
science clubs
casual reading of books on science
learning the school process for teaching science to students your age.
attempting to ask your science teacher for higher level work may make things more difficult for you as the teacher may have personal emotional issues.
your chances are roughly 50/50 at getting a positive response to getting a negative response.
keep up your coarse work.
find clubs, (make friends with)friends who do the same, make friends with those around your same age who do the same(preferably in different schools).
find a few people who are mentors, older students who need to mentor younger students for their coarse-work.
keep this all openly diariesed in your own diary and let all your family know what you are doing, who you meet, what the club names are, who potential mentors are... the more and wider you make your network the bigger the chance of getting better and more quality teaching.
many parents obsess about teenagers sexual/social development(thats normal) expect this to be other peoples baggage that you must learn to deal with because it is the opposing side of the table from where your sitting.