Student Challenge: Triple Riddle Challenge

Answer all THREE of the following riddles for a blog point.

1. What 5-letter word becomes shorter when you add two letters to it?
   
2. What letter comes next in the following sequence? D R M F S L T_
   
3. What's full of holes but can still hold water?

Submit all three answers to Mr. Koch in an envelope!

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Student Challenge: The Wolf, the Goat, and the Sack of Grain

This marvelous mind-bending scenario was submitted by Borchardt 3rd grader Brian Zhou!

A man needs to cross a river to get home. He has with him a wolf, a goat and a sack of grain. However, his boat only has room for him to carry one of the three at a time. This is the dilemna: left unguarded, the wolf will eat the goat and the goat will eat the grain. How does the man get home (across the river) in way that ensures nothing will get eaten?

You know the routine: submit your answer to Mr. Koch in an envelope. Have you checked the blog points board lately? It's a tight race!

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Student Challenge: Halving the Square

Waylon took the wrong measurements. To make his painting, he needs a square piece of paper 50 square inches in size, but he has one that is 100 square inches. How can Waylon make it the right size when he doesn't have a ruler or scissors?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: Missing Number

What is the missing number in this series?46, 10, 8229, 11, 4796, 15, 7854, 9, 7242, ???, 15

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: The Cow

This cow has the following parts: head, body, horns, legs and tail. It is looking to the left. Move two matches so that it is looking to the right.


For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: CAT TIMES CAT

Replace the letters in the number sentence below with numbers (0-9) to make the equation work (each letter represents a different number):

CAT = (C + A + T) x C x A x T

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Student Challenge: Horse Race

Two cowboys have applied for the same job. The ranch manager tells them to ride up to the top of the nearby hill. The one whose horse reaches the summit second will get the job.

The two men jump on a horse and race each other at full gallop to the top of the hill. They both want the job. So why did the do that?

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Student Challenge: Three Shirts

The friends, Mr. Red, Mr. Blue, and Mr. Black, meet for dinner. One man is wearing a red shirt, the second a blue shirt, and the third a black shirt. One of the friends remarks, "Have you noticed how we're all wearing shirts of a different color from our names?"
The man in the black shirt replies, "Yes, Mr. Blue, you're so right!"

Which man is wearing which shirt?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: Pouring Water

If you had a 5-liter bowl and a 3-liter bowl, and an unlimited access to water, how would you measure exactly 4 liters?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: Boy and Girl

A boy and a girl sit next to each other in class. "I am a boy," says the child with blue eyes. "I am a girl," says the child with brown eyes. Their teacher knows that at least one of them is lying. Which is the boy and which is the girl?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: Add a Line

By adding one straight line, can you make the following equation add up?

5 + 5 + 5 = 5 5 0

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch" and with your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: Relatives

Riddle: Brothers and sisters I have none but this man's father is my father's son.Who is the man?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!

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Student Challenge: Sunbathing Sea Lions

Some sea lions are lying in the sun on two rocks in the harbor. The sea lions on the larger rock shout over to the sea lions on the smaller rock: "If one of you comes over here, there will be twice as many sea lions in our group as in yours." The sea lions on the smaller rock reply: "Well, if one of you comes over here, our numbers will be equal."

How many sea lions are there on each rock?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school. 

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T leave your answer in the comments!

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