Lymphatic vessels transport (bus transports) lymph (students) to school.
Hmm...I need to get in
Bone marrow is the site of B lymphocyte maturation. The school cafeteria is where all of the food is made, so these represent both components. The spleen filters blood, recycle's old RBC'S, and stores platelets. The janitor represents this because he helps keep the school clean.
Oh no! There's someone inside...
The thymus is the site of T lymphocyte maturation; the classroom is where teachers tend to spend most of their time.
Sir! You're supposed to have your badge on!
I'm sending an email to sub school right now!
Badges on at ALL times!
Pathogen (intruder) tries to invade the body, but can't because of the skin (school).
Macrophage (security) recognizes pathogen and see him through surveillance cameras (lymph nodes filter lymph and immune surveillance).
Hall monitor (NKC-Promote cell lysis by direct cell attack against virus infected cells) directly confronts intruder and tries to stop him. The email represents perforin because it makes it difficult for the intruder to get around now. The badges represent antibodies (recognize, bind to antigen, much like badges try to keep everyone at school safe).