Here you can find the links to all current and past challenges. You can still earn half-points on previous challenges.
Week 1 challenges (full points until June 28th 7 p.m. UTC)
Week 2 challenges (full points until July 5th 7 p.m. UTC)
Week 3 challenges (full points until July 12th 7 p.m. UTC)
Week 4 challenges (full points until July 19th 12 p.m. UTC)