All these games come with the instruction manual and the original case.
Mario Kart DS $23 shipped and paypaled
Super Mario Bros $23 shipped and paypaled
Brain Age $13 shipped and paypaled
these prices are already cheaper than the prices on ebay.
I will put them up on ebay on sunday or monday night if no one is interested here.
I will ship them out in a padded envelope using USPS 1st class mail with delivery confirmation.
I have plenty of references here (i've bought a macbook, a mac mini, ram, games, accessories, etc) and on ebay. if you're still unsure, just do an advanced search on this forum for my posts in the "marketplace" forum.