It really is not advisable to lose that kind of weight over such a short period of time - and probably extremely difficult even if you wanted to give it a go anyway.
By my calculations (based on your current stats - calculating your BMR and then your BMR with moderate activity levels, then calculating the calorie deficit required to lose 10kg it 7 weeks and substracting that from your BMR over the same period), then I calculate that to achieve that goal you'll have to consume no more than 725 calories per day for 7 weeks - either that or severely up your activity levels (which is probably just as dangerous!).
725 calories per day is NOTHING. Most people will have close to that in a single meal for dinner. How you plan to get 5 meals out of that is beyond me. In any case 725 calories will not be enough to meet your nutritional requirements and you'll find yourself with a lack of energy, becoming weak and constantly tired, looking awful, and your body going into starvation mode, causing your metabolic rate to plummit - you won't be in a fit state to do any exercise, and you'll probably end up giving in to your extreme cravings for high calorie foods and straying off your goals.
In 7 weeks, it would be more appropriate to try to lose somewhere between 5 and 7kg. Let's say you want to go for 6kg - to do that you could go with your current exercise plan and eat around 1,400 calories per day. You could more feasibly get 5 meals out of that (although, tbh, eating fewer meals more frequently doesn't help a WHOLE lot - 3 square meals will do the job just as well, as long as the total calorie count doesn't exceed 1,400), and it's enough to provide your body with the energy and nutrients you need to function and perform the exercise you plan to do.
So if you lose 6kg in 7 weeks, then you only have another 4kg to go before you've reached your goal. Just keep your plan up and once you're 6 weeks into the school year, you'll be 10kg lighter.
Cosmetically, it'll be very clear to anybody back at school that you've lost a lot of weight, even after 6kg... that's a very good achievement, and you'll see the results.