Title: How to Make Tests for Students Using CAS Tools (such as TI-89)

Author: Bengt Ahlander* (ba@ostrabo.uddevalla.se)

Affiliation: Östrabogymnasiet, Sweden

Abstract: In my school, Ostrabogymnnasiet an upper secondary school in Sweden, I work with a math class where everybody uses TI89. The age of the students are 17 year. My thoughts about how to examine students using this powerful tool and still testing the understanding of mathematics will I try to explain here. Questions like What is the roots of the equation x^2-6x + 5 = 0? are not testing the understanding if you use TI89. But if you give the students the answer that the roots to a quadric equation is x = 5 and x = 1 you can ask the students to give example of equations that will give this answers. This is a kind of jeopardy in math and tests really if they have the understanding behind the solutions of quadric equations. We can also give questions with some solutions and ask the students to control and explain the steps in the solution. That will also test if the students can explain in proper way mathematic thoughts. I will give some more examples in my presentation from my classroom experience in my short presentation.