For boards pls don't get disheartened by the clg tests ... U can easily score in boards studying in the last couple of months too...
Even I got around 50% in the prelims !
See specifically for chemistry I would advise you to learn the p block as it is helpful in JEE too
Also organic mechanisms in the textbooks are to be route learned and as i had said earlier they are really beneficial for JEE
besides I would suggest Go through the previous 5 years question papers...but not now a week or two before exams
Physics and Maths ... you actually need to just know the method in textbook as we can't apply our own method in boards you should follow the textbook for Maharashtra boards
Also write at least a couple of practice papers (not prelims) and get them checked from your teachers