Nowadays pocket money is especially important for teenagers, because they are old enough to deside what to buy. If a girl or a boy gets pocket money from parents every week, he or she can save money and later buy clothes by themselves and not waste their parents' time. Personally, I think, teenagers in Russia should get about 400 rubles every week. They can also spend money for entertainment: cinema, café, amusement park. It is possible to organise a little tea party at home. I usually use pocket money to buy sweets, school stationery and clothes. Sometimes I need to save money to buy expensive stuff.
So, I came to the conclusion that teenagers should get pocket money and buy things themselves, because parents are not free all day.