D.B.
I wouldn't give them anything small and firm or they could choke. You can go to Walmart in the baby section and get teething biscuits. They are really hard but are big enough for them to hold in their hand and chew on. They slowly dissolve and taste like graham crackers. All of my kids loved them. You can get some stage 3 foods like carrots but again, they might not be quite ready so test the waters and see how they do. OH, and something else they loved are the baby Vienna sausages. I would just cut them into tiny pieces and they would pick them up themselves.