When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

How many times can you subtract the number 5 from 25?

There are four 3-link chains. All you have to do is join them into a big 12-link chain. For joining two closed links, one of the links must be cut and placed onto the other link for closing.

How many minimum links will you have to cut to make the big chain?

I hide my treasure in the ground, my tail is big and fluffy. If you spot me in a tree, please don’t call me scruffy. What am I?

Give it food and it will live; give it water and it will die.

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Which is the correct shadow of the bird?

I don't get anymore wetter, no matter how much rain falls on me.

I am white when I am dirty, and black when I am clean. What am I?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?