hahaha well i see that Eric and Hardgainer prolly dont approve of my suggestions, but i figured if you have problems puttin on weight you might as well take advantage of it....food tastes good as far as edible things lol i meant anything that is humanly possible to consume since i did mention eat everything you see lol.

seriously though eat alot of chicken, fish, vegetables and try to eat every couple of hours in school even though it might be a pain in the as* for you to do. Instead of packing 1 sandwich for lunch maybe make 2....or 3 and eat them throughout the day, or if your not up for that then pack a protien shake and drink it between classes but dont depend on just protien shakes as your source of protien, then at lunch time have a sandwich. That of course is up to you. Since your young you also might want to pick up some precooked chicken that you just reheat in the microwave, doesnt always taste the best but it makes it easy for me to come home and put some in and then have a meal within 4 minutes and 30 seconds. Try to up the amount of food that you take in over the next week or two overall, and shoot for at least bodyweight in protien. Make sure like i mentioned in my first post to tell us about any past training youve done, since that will help us determine what type of program would be good for you to try. hope this helps a little bit

for eric here is a sample list of Strictly non-edible things
-cars
-houses
-plastic
-rugs
-electronics
-paper
-paint chips (there's many more but ill fill you all in on those later)