A study of computer-assisted learning examined the learning of "Blissymbols" by children. Blissymbols are pictographs that are sometimes used to help learning-impaired children communicate. The reaseracher designed two computer lessons that taught the same content using the same examples. One lesson required the children to interact with the material while in the other the children controlled only the pace of the lesson. Call these two styles "Active" and "Passive". Children were assigned at random to Active and Passive groups. After the lesson, the computer presented a quiz that asked the children to identify 56 Blissymbols. Here are the numbers of correct identifications by the 24 children in the Active group:
29 28 24 31 15 24 27 23 20 22 23 21
24 35 21 24 44 28 17 21 2120 28 16
The 24 children in the passive group had these counts of correct identifications:
16 14 17 15 26 17 12 25 21 20 18 21
20 16 18 15 26 15 13 17 21 19 15 12
What is the test statistic for determining if there is sufficienct evidence to suggest that active learning is superior to passive learning?