Thresholds Investigator’s Field Manual · A DET & CW Casebook

Twelve hands-on cases about the moment just before something changes: the last drop, the last block, the last straw. A printable workbook for curious kids ages 10–12, grades 4-6.

FULL DESCRIPTION

Why does water stop getting hotter once it boils? How far can a stack of blocks hang off a table before it falls? Why does one more drop make a full cup spill over?

In Thresholds, young investigator DET and his silent crow partner CW go looking for the tipping points hiding in everyday life. Each case starts with a short story and ends with a real experiment your child can do at the kitchen table.

What’s inside (12 cases):

•     Stacking blocks past the table edge (and the surprising math behind it)

•     Watching water boil and finding its “flat line”

•     Ice, salt and why road crews switch to sand when it gets too cold

•     The angle of repose: how steep a pile of rice or sand can get

•     Surface tension: how many drops fit on a coin?

•     Strength testing with spaghetti bridges

•     Balance, center of gravity and tipping points in your own body

•     Heart-rate data, slow-moving earthquakes, and sayings about “the last straw” from other languages

Every case has three parts:

•     The Case: a short DET & CW story to read aloud, with vocabulary and discussion questions.

•     Field Work: a real hands-on project in science, math, history, geography or language.

•     Your Own File: private pages that turn the case around, so your investigator looks at their own life the same careful way. They decide who reads them.

Good to know:

•     45-page printable PDF, US Letter (8.5 × 11 in), black-and-white line art that prints cleanly at home

•     Stand-alone: no novel or other book needed

•     Ages 10–12 (grades 4–6), great for homeschool, classroom or summer learning

•     Includes a case-file cover sheet, a word search, and a grown-up guide, “Things to Listen For,” with answers to the math and facts

•     Available in a Canadian edition (metric, Canadian examples) and a U.S. edition (US units and spelling, American examples). Please choose the one you need.

•     Print for your own household or one classroom

Part of the Investigator’s Field Manual series from Perspective Detective Studios.

Observe. Investigate. Discover.