...Do you have any tips for me so I can at least get triple digit scores.
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I have my own ball and no physical limitations and if I get into triple digits I celebrate -- I only get to bowl a couple of times a year. You are brave to attempt it, and if your son is enjoying your participation then that's the most important thing. I would imagine it's like everything else, practice, practice, practice -- that's a good excuse to go more often -- and of course, have fun.