Source: Crest Precast Inc., LaCrescent, Minn.
In a plant visit hosted by Crest Precast, students of a LaCrosse, Wis., school district observed hoist pulleys, wire mesh benders, and band-saws in operation; they were introduced to principles of concrete mix design and chemical heat reaction; and, they learned that crushing produces jagged aggregates and smooth aggregates are shaped by river flows. The event culminated in each student's casting of a decorative garden paver, using multicolored rock and special stones.
The plant visit was one of several field trips provided for 17 sixth graders--ESL [English as a Second Language] students, primarily Hmong, first- and second-generation Thai and Laotian immigrants--participating in a four-week physical science course targeting chemistry and simple machines. Among other first-hand experiences students enjoyed this summer were a trip to a waste-to-electrical energy plant, attendance at an electronics robotics class offered by a local technical college, and a Mississippi River boat tour. Demonstrating the success of the precast plant visit, the sixth graders on a county fair tour corrected a 4-H judge in his use of cement instead of concrete pavers.