Reddit reviews The Boys Body Book: Third Edition: Everything You Need to Know for Growing Up YOU

I'm going to go out on a limb and say that I don't think anyone ever taught him how to properly take care of his own body. It sounds like he knows why he smells, he showers twice a day thinking that's what other people do when they smell; they shower!, and he's not understanding why he still smells despite "doing what everyone else does". It's my take on this that no one ever taught him how to properly bathe and clean his body. I don't really know how to approach this. I'm female, and when I was starting puberty I would shower... let the water pour on top of me, but I didn't actually wash my hair or body. I don't know why but I didn't. I started to smell. My Mom noticed, obviously, and bought me a book called The Care and Keeping of You. It was an American Girl book and it really helped me understand how I needed to take care of my body. I was unsure of how to ask for help because I was embarrsed and for a while just chose to live with this. Maybe you could find a male-equivalent of the book my mom got me. Buy some products and stash them in your bathroom. Tell roommate you got some stuff that he's welcome to check out and use. Leave the book on the back of the toilet as poop reading material. He might pick it up when he has privacy and might gain some info he was too afraid to pursue on his own. I know the male version exists. I'll look for the title for you.
Other things you can do to help him and not alienate him:

1. Invite him to do laundry with you. Whether it's down the hall, or at a Laundromat, offer to do it at the same time. Observe how he does this on his own and maybe you'll be able to offer him some info about detergents, water temps, sorting colors etc. Some people go to college never having touched a washing machine and are very intimidated and just need a lesson or two.
   
2. Set up a chore chart to be rotated among roommates. Everyone is involved and has a role, each week your role rotates so no one is doing the same chore every week. If someone doesn't do their share, come up with a consequence and uphold it. Maybe a rule is dishes have to be washed within 24 hours of use. If they linger into a second or third day, initiate the consequence. This is something you all agree on ahead of time, maybe even sign an agreement together. It could be something mild like the dishes get moved to the culprit's bed (dish shaming!) or maybe something as harsh as an embarrassing photo is emailed to a crush. I don't know. Get creative and hold the consequence up if the person drops the ball. Whether its smelly roommate or yourself, everyone has to play by the rules you came up with together.
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   EDIT: This seems like the closest to the Care and Keeping of You I had, but for boys but based on reading through some reviews, I think "What's Happening to my Body?" might be the best book to leave somewhere roomie can find and look through in private. If some jackass down the hall comes into your room making fun of it, just say someones mom brought it up to the dorm and you guys like to laugh at it. But keep it in the bathroom so that it can be looked at when smelly roomie is alone. He knows he smells, and I'm sure he wants to know how not to smell despite what he says. It sounds like deflection because he is shameful, but hides behind pride.

Here is a link to the American Girl book in a boy's version:

http://www.amazon.com/gp/product/1604335742/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=1944687762&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=0545237513&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1BKGX26M5BQH84M3H111

I got this for my 10 year old son. I like that it covers other ground like social relationships, good general hygiene and general self-care in addition to the stuff on puberty. Having a go-to book in their possession is really important -- if they are curious about anything in particular, they can read up on it discreetly. As open as I am with my son, I know he is still shy/embarrassed to talk about certain things.

https://www.amazon.com/Boys-Body-Book-Everything-Growing/dp/1604335742

This article has a slideshow of options: http://www.todaysparent.com/family/family-health/puberty-books-for-boys/

I don't have experience with this yet but I saw this book on amazon the other day and perhaps it could help your kiddo? I imagine he is on the younger side for the book but still in appropriate age range.

It's Not the Stork is a great introduction to the topic of reproduction. Boy's Body Book looks good, but I haven't read through it yet.