The difference between the group means in a pretest-posttest control group experimental design can be tested for statistical significance most precisely by
a. analysis of variance of the groups' means on the posttest.
b. separate t-tests of the prepost difference for the experimental and for the control group.
c. analysis of covariance on the groups' posttest means with pretest as the covariate.
d. analysis of variance of the mean changes from pre- to posttest for the two groups.
C
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Mr. Nunez wants to help his students develop the concept of Equality of Parts in Fractions. Which of the following activities should be introduced last?
a. partitioning objects such as cookies or clay b. using tangrams to model equal fractions c. using fraction circles to model equal fractions d. drawing partitions on outlines of geometric figures
Mr. Antonio has been teaching for many years, and he has come to the conclusion that by the end of the first month of school, he already knows enough about the students' academic abilities that he can predict their final grades. Mr. Antonio can best be described as having:
a. a fixed mindset about the students as learners. b. low self-efficacy for his ability as a teacher. c. no extrinsic motivation to help his students succeed. d. optimistic but realistic expectations for student performance.
A school district examines a program that uses mentors to help very poor readers improve their reading performance. The children in the program are at the 4th percentile at pretest. At posttest they are around the 20th percentile. While it is possible that the program made the difference, another reason for the change in scores could be:
a. History b. Regression artifact c. Multiple-treatment interference d. Differential selection
In the process of investigating—counting, estimating, and measuring are examples of ways students apply mathematics in scientific inquiry by:
A. quantifying the real world. B. organizing and interpreting data. C. using patterns and relationships. D. being persistent.