The site under scrutiny is actually very good at keeping advertisement, bots, and child-unfriendly items off the screen. This is due mostly to being part of a research center website, specifically, the Space Telescope Science Institute. For this reason, the site is extremely informative about esoteric facts. The specific web page, which discusses Chaos Theory and how fractals and the Butterfly Effect both relate to said theory, is child-friendly, and contains no advertisements. The site also contains pictorial depictions of concepts. I recomend this site as well as the Chaos Theory page, for research into complex astronomical and mathematical concepts.
About this site
The Space Telescope Science Institute enables excellence in astronomical research by optimizing the science from state-of-the-art observational instruments in space.