The H&P is a good idea. If you know how to take bp, then you or your school can purchase cheap bp kits at a pharmacy. Otherwise, you can ask an EMT, paramedic, or ED Tech to demonstrate what they do in their jobs. Since many people working in these areas are premeds as well, they can say they volunteered their time to teaching 7th and 8th graders.
You could also have the students act as an admissions committee. You can make up the applications and have the students meet in committees, then make a decision about acceptance, rejection or waitlist.
Some fun simple experiments include the egg drop, the super needle balloon, and the simple motor. All of these experiments are on the web. I'll briefly describe each.
Egg Drop
Materials- 3 sheets of paper, one yard of tape, scissors, 1 egg.
Purpose of the experiment is to use the allotted materials to make a container for your egg. The container should be strong enough to protect the egg when it is dropped from 2 meters. Teaches students about safety belts and airbags.
Super Needle Balloon
Materials- A pack of wooden skewers, a bag of balloons and petroleum jelly.
Purpose is to blow up a balloon with air. Take a skewer and insert the pointed end of the skewer at the densest part of the balloon. At this point the balloon should have popped because the petroleum jelly acts to make a seal. With a new blown up balloon put a dab of petroleum jelly at each of the densest part of the balloon. Reinsert a skewer at the densest part of the balloon at one end, go to the other side and exit the balloon. Take the skewer out and pop the balloon for effect. Teaches students about proteins and permeabilty.
Simple Motor
Materials- Cup, tape, copper wire, 5 magnets, leads, 2 paper clips and a battery.
Purpose is to make a simple motor.
Teaches students about magnetic fields, circuits and balancing.