New TikTok video: How one student helped me see arithmetic sequences differently

I start this topic off by looking at Caesar shift ciphers. Moving the letters +3 etc. then look at what happens when we do this to times tables. Showing that arithmetic sequences are like ‘Caesar shifts’. Great to map them and link it to straight line graphs and y=mx + c

95*4+19 = 399 95 because you are doing 100 terms (and have already done 5) *4 because that is the sequence +19 because that is where you ended (after the 5th term)

This is SO GOOD!!!

@AnneHasse Something I miss about the Wakanda learning community in which my mind was frequently blown!

Another way to do this, though maybe it's more complicated because you need to know the median of this list, is to know that the first + last numbers in the list divided by 2 will equal the median. Here, the median is 201, so (3 + x)/2 = 201 3 + x = 402 x = 399

I like your t shirt!

-1 is the 0th term The common difference is 4 The 10th term is -1 + 10(4) = 39

I don't find anything in teaching more rewarding than learning from a student.

Wow - that's exactly how I've always taught arithmetic sequences: nth term is common difference times n, plus an adjustment so the first term is correct. Sum is "first plus last, times number of terms, divided by 2" English instead of formula.