ESTIMATION OF EXPONENTIAL EXPRESSIONS BY HIGH-SCHOOL-STUDENTS

This study investigated how students with a familiarity with exponenti ation intuitively combined information about bases and exponents in ex pressions of the type a(n) to estimate the magnitude of these expressi ons. Three base values (5, 7, and 9) and four exponent values (2, 3, 4 , and 5) were combined to create 12 expressions. A student's task was to depict graphically an estimate of the magnitude of each expression. Qualitative and quantitative analyses conducted on the data revealed four different models of magnitude estimation: an exponential model (t wo subjects), a multiplicative model (14 subjects), and two additive m odels (19 subjects). (C) 1995 Academic Press. Inc.