Thanks for the contributions thus far.

Dear WmTrevor,

The hole in the ground reminds me of the plane that crashed into the cemetery directly on the border between North and South Dakota, one thirdof the passengers were Catholic and two thirds were Protestant, where were the survivors buried?

The tide one I used a few weeks ago. Always gets them for bit. Good puzzle that.

I managed six.

2-Ecuador, 3-sheep, 4-November, 6-canines, 9-New Zealand (lived there), 10-orange I think.

Dear Lexi,

I am certainly not adverse to these types of puzzles, I enjoy having them posted here and trying to nut them out. The reason for my original remark was purely practical, the hanging man over a pool of water required me to answer about 50 queries from the kids. When you have two or three groups going at once it can be a bit hard to handle.

Was Yuyutsu's answer the one you had in mind? Or was it old age?

Dear spindoc,

This has to be one of my favourites and used it again last session. Oh what fun, especially the looks on their faces when you first deliver it. It is probably cruel when you know they almost have it and you say "you just aren't getting it" then restate the question, it throws them all off completely.

Another favourite is the two jars of exactly the same quantity of nutrient fluid. Into the first we put one amoeba which divides once every 3 minutes. It takes 1 hour and 57 minutes to completely fill the jar. In the second we place two amoebas, how long does it take to fill it completely?

Those amoeba - one minute 54 seconds.

Beautifully counter-intuitive...

csteele, try this one then.

James lives in Sydney, he has two girlfriends, he likes both equally.

So when he goes on dates, he goes to the train station and lets the train decide which he visits, the first train to arrive is the one he visits. One girlfriend lives on the northern line, the other on the southern line, both equal distances from his train station. Each train arrives at 10 min intervals precisely.

He finds himself visiting the girl in the north eight times out of ten, why?

The government of Tulpania declared Mt. Kunusuma as a nature reserve, totally out of bounds: nobody ever scaled it and a whole regiment guarded its perimeter day and night against trespassers.

However, Tulpania ran into a bad deficit and when Bill Gates offered them $2b for allowing him to be the first person to climb Mt. Kunusuma, they could no longer refuse.

He started off climbing in the morning and by the evening when he reached the peak, he found there a cabin. He opened its door and found 3 decaying human bodies inside.

The Prime-Minister of Tulpania insisted that he was the first ever to climb Kunusuma - and he did not lie. How come?

Spindoc, the South-bound train always arrived 2 minutes after the North-bound train.

Dear spindoc,

I think the answer is that although the frequency of each individual train is ten minutes the South bound train arrives two minutes after the North bound one leaves the station so unless he arrives within that two minutes out of every ten he will be headed north.  Not bad. Into the kit bag. Thanks.

Dear Pericles,

Indeed it is. One I reserve for the slightly more mathematical students is how many people must enter a room before the chances of two of them having a birthday on the same day of the year is better than 50%?

It has won me more than a few drinks in bars.