Math with M's class

M had been complaining that math was too easy and boring, so I arranged with his teacher to take a group of better students (8 or fewer....I'm not crazy!) and do some math enrichment. So today was my first lesson. They had just been introduced to 2 digit by 2 digit multiplication, so we worked on it for a bit, then I introduced 3 digit by 2 digit. They mostly got it and a couple of the girls were really excited by how it all worked. It's fun to see those lightbulbs turn on in their heads!

Then we still had some time left, so we played 24. You get a card with 4 single digit numbers and you have to use each of them once (and only once) to make 24 - you can use +, -, x, /. So if your numbers were 1, 3, 5, 8 you could do

3x5=15
8+1= 9 -> 15+9=24

or

5-2=3
8x1=8 -> 3x8=24

I'm going to do this every Friday morning, so I'm keeping my eyes out for interesting math bits to do with 4th graders.