|Janitors (2011) by Tyler Whitesides|
It turns out that Marv Bills and Walter Jameson do more than mop floors. They're fighting toxites, little creatures invisible to most people unless they've been exposed to magical glop, that want to sap the smarts out of kids. Marv and Walter's problem though, is that while they want to help the kids, the BEM, Bureau of Educational Maintenance, has withdrawn support for them, as if the BEM actually wants kids to get stupid. Not knowing why the BEM has withdrawn support, Marv, Walter, and a handful of other "rebel janitors" continue to use glopified equipment, struggling to fight back the toxites on their own. But when the BEM start coming after them, the kids want to step in and help.
What will happen when the BEM start coming after the kids?
The book is a bit long for its target audience, but I think it would be an enjoyable read for most upper elementary aged readers.