Memory in Life After 60

I have been taken a course in weather forecasting for the last month. Trying to prepare for the final exam is a challenge. It has a lot to do with memorization. The strange thing is, some of the stuff I can remember fine. Other parts of it I get the wrong answer every time. I am trying word association games to see if it will help but some of them just don’t stay in my memory. Out of a test bank of 207 questions, they will only ask 50. I sure hope they don’t ask many of the ones I am having trouble with. I hate tests.