6 yr old competitive/justice rage

[basilrac]

My first born is now 6 yrs old (boy).  There are two brothers in the house ages 5 and 2.  The 6 yr old has quite the neurological medical history but in spite of all that cognitively his mental age is about 8 1/2 (testing a few weeks ago).  His fine and gross motor skills are even within normal range though weak.  He has had many medical procedures forced upon him and fought the process every step of the way - naturally - since birth.  Now that you have some background my behavior question is about his competitiveness - while this drive has no doubt kept him alive it manifests in not so pleasant ways lately when playing with friends (last surgery two months ago).  All day long in EVERYthing he does he is constantly asking if he is the fastest, the first, the most -- essentially the best.  He will loose control - as in growl and shout and beat on his brother when he is embarrassed coupled with loosing (his perception of loosing) or some kind of injustice (like when another kid overheard the answer and gave the answer in a game of hangman and he felt this was not fair and caused him to loose).  While I feel his pain and admire the way he jumps to his assignments asking if it is a challenge and then asking for more challenges -- I cannot have him raging on in a classroom (by all neurological checks the rages are not related - yet - things change fast around here).  How do we manage this drive and help him to keep it in perspective?  Is it something normal that will pass with love, patience and discipline?  OR - is it a more serious cry for help due perhaps to feelings of inadequacy over the physical differences and limitations that he is perhaps beginnning to recognize?  How do I help with that?  (by the way .. he has improved some at home I am just very alarmed that the outburst happened at Church today and could happen at school where it will not be tolerated though -- two years of Montessori and one yr K in Canada and two outburst - because of age requirements here in the States he is in K again - not helping but no outburst -  (Church class kids are mostly in grade 1 - again not helping).