1. Today we face the dreaded heads and legs mathematical pickles!

2. At the farm, there were some
cows and chickens. I counted 8 heads and 26 legs. How many
cows were on the farm?

3. Draw a circle for each animal (8 heads).
Remind them that each animal will have one head, so the number of heads is the total number of animals.

4. Add 2 legs for each animal.
Count up the legs used. Remember we started with 26.
Every animal will have at least 2 legs, so this is a great way to see how many extra legs we have.

5. Ahh...since every animal has at least 2 legs…
Subtract the legs used.
You have 10 legs left over.
Every animal will have at least 2 legs, so this is a great way to see how many extra legs we have.
Ahh...since every animal has at least 2 legs…

6. Distribute the left-over legs 2 at a time.
Put two legs on animals until you run out of legs!

7. The four-legged animals are cows!
Put two legs on animals until you run out of legs!
Count the cows and chickens.

8. Try this one!
I saw birds and squirrels at the park. I counted 9 heads and 24 legs. How many squirrels did I see?
There were 11 squirrels and 6 birds. How is the logical thinking going? They will need to think critically to master this part of the test.

9. Finally, we will put it all together!
SHOW WHAT
YOU
KNOW!
At this point, distribute the “Heads and Legs” work page. The front has 6 problems for them to solve. The back has four problems with “problems”! Students need to try to work the four “rejected” problems, then determine why the problems did not work.

10. You will be given 3 “heads and legs” problems to work.
You will also receive 3 problems that were rejected.
Solve the first 3, then explain why the last 3 will
NOT work!