University of Cambridge
University of Cambridge: Nrich: Hand Span
Use this one page website to practice measuring things using nonstandard units of measurement. There is a solutions page that is right at the website for more information.
University of Cambridge
University of Cambridge: Nrich: Dining Ducks
This problem will quack you up. On this one page website use those problem solving skills to check the reasonableness of your answer. The solution is available right at the website.
University of Cambridge
University of Cambridge: Nrich: A Rod and a Pole
At this one page website work on this challenge using your very best problem solving skills to find a reasonable answer. Actually, there are a number of solutions. When you find yours check the website to see the solutions already listed.