Identify the 2 Possible Threat to Internal Validity:

An educational psychologist designs a demanding but fair spelling test that can be administered to grade school children. The test is found to be valid and reliable. A researcher selects the test to help evaluate a "cognitive" approach to teaching spelling. A 5th grade class is tested prior to being taught the new method and then again after the new method is taught. The children show improvement on their spelling scores from the first to the second test administration, suggesting that the program was effective in helping children to learn to spell.

THREAT 1:

EXPLANATION FOR THREAT 1:

THREAT 2:

EXPLANATION FOR THREAT 2: