Here’s a pair of classics – and updated links for those of you who may have been frustrated with the blogroll…
These are Elementary School problems – great, open ended tasks for grades K-5 from the NCTM. They are often organized by theme, and have been archived for years… Of course many feature an American context, but there’s LOTS to choose from here!
The complement to these for our intermediate colleagues (grades 6-8) are the Middle School Problems. And these ones come with answers… 🙂