Amazon sells pretty much everything these days, including science supplies. A search of just "microscope slide kits" turned up several pages of introductory through professional kits for individuals and classes and a wide range of suppliers.
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(413-527-3932). Berkshire biological supplies living organisms to school systems for two decades now, and specializes in kits and materials for grammar school and high school science levels. Prices for specimens are extremely reasonable, and all specimens are shipped with care to arrive in good health for your projects and experiments.
CBS has a full range of chemistry and biology lab supplies, but they are often packaged for classroom or industrial use. The catalog is pricy (but almost worth it for its own sake); you get a coupon for the catalog price which can be credited against future orders. CBS will not sell chemicals or preserved specimens to individuals but does have a homeschool policy.
Started by a group of scientists who realized that many of the science kits flooding the homeschool market were not well-designed, the kits offered by eScience labs emphasize safety as well as quality, providing both hands-on equipment and video virtual experiences. Their lineup includes a complete AP Biology Lab kit for an individual student (available 1 June 2008).
Similar to Caroline Biological Supply: provides classroom kits for life and physical sciences, K-12, as well as professional supplies to college and industry research facilities. Most kits are for multiple student use. Site includes lab demonstration suggestions and resource materials as well as merchandise.
Both an online store and a physical store (in Parkville, MO), the online store carries basic science equipment, kits, and games, including chemicals in small amounts suitable for home experiments, lab equipment (glassware, sclaes), telescopes, and microscopes.
(1-800-860-6272). Started by a family that itself had trouble finding supplies in the 1990s for their homeschool science curriculum, this is a great resource for the homeschooler, with experiments, kits, and curricula for primary through secondary levels. You can also get individual items such as microscopes, chemistry lab bench supplies, including chemicals hard to find in small quantities elsewhere, and some that many companies may not ship to individuals.
Do-it-yourself enthusiasts for both science and technologiy, MakerShed carries supplies for crafts and hobbies as well as science and robotics. Similar to HMS Beagle and Home Science Tools, but with more DYI equipment geared toward older students and adults. A good source for serious science lab equipment.
Natural Science Indudstries Ltd> Dept. C, 51-17 Rockaway Beach Blvd. Far Rockaway, NY 11691
NSI makes the Smithsonian chemistry kits, many one-experiment kits, and also sells replacement components at inexpensive prices. They do not sell directly to the public as far as I can tell, but their products are available at many educational stores and from many online suppliers (just Google "National Science Ind"!)
Science kits, supplies, classroom activities, recommended material lists. This supplier has expanded its user base to include individuals; printed catalogs are available only to certified teachers and homeschoolers, but the site contents and suplies are availab to all.
This company markets its science supplies at educational toy stores. Their line includes most of the chemistry lab equipment recommended for a home lab, including thermometers, test tubes, stoppers, pipettes, flasks and beakers.