The Big Chunk of Ice in Bloomington, MN

It wasn't the diamond as big as the Ritz, but it was a pretty big chunk of ice, and it got the precocious pranksters of The Mad Scientists' Club entwined in an international intrigue only the intrepid investigators of Interpol could unravel.
Take the seven young mad scientists of Mammoth Falls, stick them in an antiquated blimp bound for the Austrian Alps, along with two "hep" college girls and a zany professor of mysterious Romanian origins - and you have the makings of a high-flying adventure!
If you're not already a fan of super-brain Henry Mulligan, dinky Dinky Poore, fat Freddy Muldoon, and the other unpredictable troublemakers that populate this series of mad adventure stories, you will be, once you read
The Big Chunk of Ice.
The fourth book in
The Mad Scientists' Club
series, written by Bertrand Brinley in the 1986, but first published in 2005 by Purple House Press.