One of the important uses of trigonometry has to do with simplifying calculations with vectors, and therefore Trigonometry is Essential to Physics
mathigon — Philip Legner’s beautiful web site on maths
plus magazine — an online magazine dedicated to explaining mathematics
chalkdust — excellent magazine for mathematically curious people
madras college activities page — madras college is a school in st andrews with what looks like a good maths department
number gossip — everything you wanted to know about a number but were afraid to ask!
billionaire mathematician James Simons — making money by taking a scientific approach to markets — please also see How to become a quant below
The Good Thinking Society promote maths achievement, and their aims are broadly in line what I believe should be the purpose of education
a mathematician’s lament — Paul Lockhart on what is wrong with the way maths is taught in the USA but could equally be said of here
interactive and dynamic
cut the knot — good for interactive puzzles — the creator of the site, Alexander Bogomolny, died in 2018
geogebra — dynamic geometry for everybody
These allow a more complete understanding of mathematics — “definitional”, graphical, and numerical — to be developed, all in the palm of your hand.
SQA seem to disdain the use of these tools, and I can appreciate reasons for doing so, but at the same time I really love my GCDs.
HP Prime — this could be the ultimate graphing calculator, and the site pointed to has a lot of resources to get good use from it
TI Nspire CX II T CAS — CX II T the new kid on the block
Casio fx-cg50 — graphing calculator
numberphile — videos about numbers and stuff
3brown1blue — for Advanced Higher topics and beyond
ridiculously large numbers — by David Metzler
the philosophy of mathematics — by Ray Monk
I cannot think of any podcasts that are good for high school maths. If you know of any please let me know. On the other hand there are many excellent science podcasts, and I encourage you to follow and listen to these on a regular basis — it’s amazing what you can learn from this source.
Similarly I do not know of any good blogs for high school maths. There are many for maths beyond high school, but none that I know of aimed specifically at school students. Again please let me know if there are any that you follow and read on a regular basis.
For instance top 25 high school maths blogs are all American and more aimed at other teachers rather than students. I really want to point to a blog which is aimed at making maths clearer for students.
quotations on the subject of maths
today in science history has a page of mathematics quotations
how to become a quant
Michael Halls-Moore has a very informative site on all things to do with becoming a quantitive analyst. See A step-by-step guide on getting a job as a quantitive analyst and Understanding how to become a quantitive analyst. Basically you have to be prepared to study a lot of maths.