Mathematics.
13 + 5 =
13 is made of 1 ten and 2 ones. So
13 + 5 = 10 + 3 + 5
Then add the ones together to get the answer,
13 + 5 = 10 + 8 = 18.
The students may have described this to you at home as the 'ninja chop' as I encourage the students to physically draw a line between the tens and ones to create a column and better organise their thinking. The other strategy covered was using doubles facts (memorised sums like 2+2=4) but also identifying when we can use a double and just add one to get the answer. For example;
3 + 4 = 3 + 3 + 1 = 7
This one was a little trickier and I was just happy to see the students using their memorised facts to help with with their computation speed. Thank you to everyone who practiced at home but 7 +7, 8 + 8 and 9 + 9 is still causing a few problems!