Brett and I store our extra batteries in a drawer in the kids playroom - this was a decision we made BEFORE our children started opening drawers. But, they have learned not to open the drawer, so we have left them there (although with a new baby coming I might be rethinking).
However, today for whatever reason, Peter DID open the drawer and started to pick up some batteries when Brett stopped him.
Brett - Peter, we do NOT play with batteries.
Peter - Why? (A question I am beginning to HATE)
Brett - Because, Peter, batteries aren't toys.
Peter - Then why do so many toys need batteries?