Need advice/help/ideas on how to solve problem?

you said you're participating in several extra curricular activities, thats the point. meaning endulging such extra activities gets your body system tired. and you spent lesser time on paper works (homeworks/ignments). you do sometimes neglected it. try to lessen your extra curricular activities, specially now you're a senior, concentrate more on the lost time in studying and reading your previous lesson as part of reviews, theres still time to catch up.,(if you really want to be a valedictorian, you can do so), determination and ambition to finish your studies with honors should always be your first priority. time management is important. good luck