The Adventures of Penrose the mathematical cat by Theoni Pappas

The Further adventures of Penrose the mathematical cat by Theoni Pappas

MindWare's Venn Perplexors Level B by Evelyn B. Christensen

175 More Science Experiments to amuse and amaze your friends by Terry Cash, Steve Parker, and Barbara Taylor

Science Experiments with Magnets by Sally Nankivell-Aston and Dorothy Jackson

600 Manipulatives and Activities for Early Math y Diane Bello Peragine

Math Practice for Beginners by Shirley B Spriegel, M.S. Ed.

https://www.math-salamanders.com/

https://littlebinsforlittlehands.com/

https://www.stevespanglerscience.com/lab/experiments/

https://www.wired.com/2011/06/how-static-electricity-works/

https://www.explainthatstuff.com/how-static-electricity-works.html

http://www.momswhothink.com/kids-crafts/how-to-make-slime-without-borax.html