Doubting Myself !

I have been teaching these 2 boys for years now and I used to think that with time,it would be very easy to do it all.

Today,it was very sad.It took me 2 hours only to explain the difference what 6 n half in terms of giving marks on a test meant and what 6 n half dozen meant.I explained that in one the half stood for 0.5 and In another it was half a dozen,half of 12 and that was 6.What baffled me was why an 11 yr old coudlnt just get it? I was so frustated from explaining it again and again,I kept yelling at the top of my lungs and smacked him on end at every mistake he made over and over.

Sometimes,I think Im not a good teacher.They do get the best grades and do well but it comes at such a price at times.I dont like when I go wild.Sometimes I try to be patient,I count till 20 but what is and how is one supposed to do when teaching something that just doesnt seem to get through.

I know the kid can sometimes be cloddish but then I should be smart enough to get through to him a better way.My dad used to be like that.He hit us when he got frustated teaching something.But then unlike my dad,I know what Im teaching a 100% and different methods of the same problem.Back then,my dad looked at the reader and tried to teach us.I did get 50s in maths back then but I never understood math at all.But now I make it very simple but still he doesnt get it.

Im so tense and worked up,my pressure goes sky rocketing.What should you do,if the kid looks for easy way out and not interested in studying at all? How do you make a child take his studies seriously and not just play around? I have given every possible lecture on earth on the importance of studying on time and making time to play,I have tried being strict,I have tried being relaxed but he takes comfort in behaving like a toddler.

If anyone has any clue as to what else can I do or if Im wrong in being so strict,do tell? The problem lies in Math alone coz the rest he just learns by heart .

I actually hated myself today,I felt I was being all rude and harsh and I hate being that monster.