Peg board? Chalk board? what kind of board?
You could make a dream catcher type, take an embroidery hoop and wrap yarn/string all around the edge, then using a needle with the yarn/string hooked through and pull it through random parts around the embroidery hoop until you're happy with how it looks. Use little clothes pins to hold pictures/messages in place
Or you can use a cookie tin and magnets, use some hot glue or E6000 to attach some pop tabs or string to the back for easy hanging.
You could use a piece of cork board and push pins
Here is a couple I have made