Two 38 mm spherical lenses; one is a double concave, the other a double convex, each with a focal length of 150mm. When placed together the net focal length is zero. (1-1/2" x 1-1/2" x 1/4"; .005Ib).
Great for optics experiments in the lab or classroom.
With 23 hands-on experiments, you can investigate specific weather phenomena as well as the climate system in general.
Comprehensive collection of 30 fossils.
View the glory of space with this hi-tech telescope set!
The Ball of Whacks is the perfect creativity tool for innovators, artists, engineers, writers, students, and you!
Command robotic creations with this cool construction kit!
Build a model car that runs on hydrogen gas using a unique reversible fuel cell!