Most of the people here who are recommending against it probably never tried it at that age or close to it, in a way i think they are just jealous they never did, but i think shrooms would be better for his first time though.
first time for me at 17 with my brother 13 we tripped to led zepp... I was there with him so he was ok.
first time i tripped i was 13 on 5 hits. (thanks big sister) i had a lot easier time tripping when i was younger. its hard to say if its a good idea or not to someone else at that age though, but its hard for me to encourage anyones first time. psychedelics arent for everyone. i know it has shaped who i am now and i regret nothing, im quite grateful for my early trips. i feel like it made me a consious human being early in life.
i would NEVER. under any circumstance give my brother acid. i am only 16, and i still consider myself too young for acid. although tempting, i resist the urge. I feel like i am able to handle it easily, however i feel like i still have alot to experience throughout my life, i should save the most exciting for last. AND if your brother were to manage to hurt himself, or do something stupid on a bad trip. how could you live with yourself? if i were to ever be responsible for the corruption or hurt of my brother id consider myself a worthless peice of shit. dont introduce your 14 year old brother to that shit. if acid is right for him, it will find him by itself. you don't need to force it into his life.