# Two Puzzles to Stretch Students’ Logical Thinking

Riddles are a fun way to get students thinking logically and tackling problems that can seem overwhelming at first. In this TED-Ed riddle, students are put in the position of a famous mathematician who has been jailed by his king, but has a chance at freedom if he can figure out which of 12 seemingly identical coins has been counterfeited by a corrupt official.  The video sets up the conditions of the riddle at the beginning and the answer comes at 1:18.

This second riddle is a classic river crossing problem with unique limitations that force students to think through various options. The video even offers some problem solving strategies, that could be used as clues. The answer comes at 1:04 in this video.

• Hillary Clintub

When I was a toddler, my dad and I would lie in bed on lazy Sunday mornings and make a game of solving riddles like this. Dad always loved to challenge me with logic problems of appropriate difficulty and praise me when I solved them. I loved earning his praise, too. When I solved a problem, I often challenged my mother with it. She hated that. She really wasn’t into logic. She was more into emotions than logic.

• Kelly

I think I would have first weighed six coins vs six coins. Whichever group of six was lighter, I would have taken those and weighed three vs three. Whichever group of three was lighter, I would have then taken those and weighed one vs one. Either the lighter one is fake, or the one not being weighed is fake.

• Pingback: Two Puzzles to Stretch Students’ Logical ...()

• Pingback: Two Puzzles to Stretch Students’ Logical ...()