Hey just want to address a few things:
- You need to believe that you can do this. No one is intrinsically stupid or dumb. We can be lazy which may result in results we don't wish for. However you are looking for help since you've realised something you don't like, thus making you not lazy and quite smart, since not everyone will look for help. I believe in you, I know you will do the very best. If no one else says this to you, I will: I believe in you. No one was there for me when I didn't believe in myself but once you believe in yourself, confidence and good results will come.
- Regarding how much time you need to set aside for extension 1 in order to not feel burnt out or underprepared: I would suggest not making time spent studying a goal. You should have a goal where you decide what things need to accomplished by (a particular chapter/revision notes/practice paper/topic focused questions). Additionally, time should limit how long you do a task. Take as long as you need to to finish it. Just make sure that you spend your time without distractions (without lyrical music, bright flashing lights, etc.). If your workspace is really noisy, pink noise will help since it almost blocks out everything (it works for me and I have a short attention span). I spend about 4 days doing maths advanced, 5 days doing extension and 6 days doing extension 2 (since I take that unit). I suggest a blend where you do one day where you finish all advanced content for the term so you can focus more on extension 1. If you'd like more info on this, just dm me.
- Homework may be called
homework but it doesn't need to be done at home. Recess and Lunch as well as class time (during Maths, you don't want to maths in chem for example) are excellent times to begin on homework and assignments. I find it easier to get work done at home when I do a little bit in school during the assigned class, even a little bit of planning goes a long way. If you need more info, just dm me.
I think I've covered everything. If you need some resources, I'm happy to send some your way.