i have an old Kenmore sewing machine Model # 148.12071. When I move the needle up and down the needle is hitting the bobbin casing and kicking it out. I can't figure out what is causing this. Can anyone tell me???:

 

Hi and welcome to the forum! Could be a number of things. Did it just start doing this suddenly or is this the first time you're using it in a while?
Did you put the needle in correctly, is it pushed all the way up? Is it an old needle? Try putting in a new one. Sometimes they just get bent. Try re-threading.
Could be lint, a piece of thread or the broken tip of the needle stuck in the rotary hook. You might have to disassemble it to check it out and give it a good cleaning, then put a drop of oil in the hook.
If it's none of these things, could be the timing's off and it's best to take it to a repairman to fix that.