elementary demos

[kowalskil@alpha.montclair.edu]

On March 8 Dwight K. Souder wrote:
> Our school's elementary had asked me to have my students come over and 
> present the elementary students with some hands-on science demos. My 
> students will be going into 1st - 3rd grade classes and will be in there 
> for about 1 hour. Can anyone offer some advice?  Can anyone offer some 
> science demos that are safe, interesting, and don't require any "special" 
> equipment?

1) An electromagnet based on a D battery. Use a big nail as a core and at
   least 50 coils of thin isolated wire.
2) A simple telescope from two lenses, for example, f1=30 cm (objective)
   and f2=5 cm (eyepiece).
3) Measuring the "half-time" of cooling. For example, the same amount of
   hot water in a big cup and in a flat plate. Teach them how to organize 
   data into a table and how to describe them clearly with words (writing 
   a report with a picture?).

Ludwik Kowalski