khan academy links

for grade 12 math students, i have this: Intro to Probability
for grade 11, have a look at this: Law of Cosine, intro and proof
my ib physics grade 12 students, have a look at these: Big Bang (intro), C(osmic) B(ackground) R(adiation), Stellar Evolution: Birth of Stars, Stellar Evolution: Red Giants, Cepheids, Cepheids 2, Stellar Evolution: Massive Stars, or simply a list of all videos on Astrophysics & Cosmology.
for my grade 11 physics students, have a look at acceleration, and Newton's 1st law, and Newton's 2nd law of motion.