This paper presents the final report of an evaluation of an in- service television training program in mathematics for elementary teachers. Teachers in the evaluation sample were tested with three separate and independent mathematics achievement tests in the areas to be covered by the telecasts. The tests were The ETS Cooperative Arithmetic Test, The ETS Cooperative Structure of the Number System Test, and a special Insightful Arithmetic Test. They were administered before the telecasts and, in alternate forms, after the telecasts. During the telecasts, the teachers were given specific unit tests at the appropriate times. All tests are either discussed in the paper or included in the appendices. In addition, each teacher was given a copy of an Instructional Activities Survey (covering Teachers' Background, Attitudes Toward Mathematical Activities, and Attitudes Toward Teaching Mathematics) and was asked to return it after completing it. Pupils of some 45 selected teachers in the sample were also tested before and after the telecasts, but this data was not analyzed. School districts included in the evaluation included a rural, a moderate-sized city, a large city, and a suburban system. Overall, the present findings lend themselves to two major interpretations. Either the teachers did not benefit from viewing the series of telecasts in accordance with a prior expectations, or the tests used in the evaluation did not measure those variables on which a change did occur. An explanation in terms of a combination of both these reasons is also possible. The results of the Unit Tests do suggest that the teachers did not benefit greatly from the televised instruction. It is noted that generality of the findings is limited by a high drop-out rate during the course of the telecasts and by lack of control over conditions under which they were viewed, re-viewed, and supplemented by independent study. It is further noted that economic restraints on the project—the inability to evaluate the telecasts while they were being developed—may well have limited the effectiveness of the telecasts themselves. Includes Cooperative Mathematics Tests, Handbook, 1964.