This is a chart I used with my class after I had introduced the term "factor". I had my students fill in the factors on the chart for each number 1-50 (including 1 as a factor). Afterwards I had them color all of the numbers with only 1 pair of factors and introduced the term "prime". Then they colored the rest of the numbers a different color, and we discussed the term "composite".
You can have this be a partner or group activity, or this can be used in math centers.
This is a visual chart for distinguishing between prime and composite numbers 1-50. Afterwards you can discuss the other notable patterns with the factors.