(Kelly of the Clue Crew gives the clue from a lab.)  Stretch a balloon over a glass, secure with rubber bands, then place a straw on top & you have a simple version of this device that measures air pressure
[DOC] [TLE] Full text of "ERIC ED428964: Newton's Apple Teachers Guides ... [PAR] If you have any questions or comments, please let us know-we welcome your 
feedback!