This animal testing for kids website [please don’t be insulted!] gives good background information to what it is and its history.

https://kids.kiddle.co/Animal_testing

*Health Warning!*  Be wary of the views of pressure groups, for and against, as they all have agendas they are trying to promote.

The Cruelty Free International website makes the case against testing.

https://www.crueltyfreeinternational.org/why-we-do-it/arguments-against-animal-testing

A more balanced view here from Planet Science.

http://www.planet-science.com/categories/over-11s/technology/2011/09/animal-testing—the-facts.aspx

Animal testing on the ProCon.org website.

https://animal-testing.procon.org/