Unusual Activities

[lkh5650]

Hi, for harvard application, it says

"If you consider anything about your academic record or career pattern to be unusual, please explain. Account for time (three months or more involving military service, travel, family responsibilities, etc.) not covered in preceding questions."

Should I put anything on this section? My mark was excellent in 1A, 1B,2A but drops significantly in 2B (over 10%) and goes back up in 3A, 3B, (i am in 4A now)

Should I explain why this happened? this is actually solely due to lack of interest in school in 2B, i was a mess, didnt go to any classes, didn't manage my life at all, just total trash, i guess i was mentally having difficult time... my grandma passed away and stuff

i dono if its worth it for me to explain this sudden drop of my grades, and if so how should i approach and say it so that it doesn't sound bad?

Also it says

"Please describe any project(s) that required independent work on your part and/or laboratories in which you have conducted independent research."

does my 4th year design project (thats honors work i guess,, with 3 other classmates) that I prepare for a whole year work?

thanks guys!