I first tried this with children in Key Stage 2, but it also works with reception-aged children with a liitle patience. The children love it.

Split the class into two / three teams. Their aim is to reach the opposite side of the hall.

Each team stands in a line at one side of the hall with their legs spread apart. The person at the back then crawls underneath all of the pairs of legs and then becomes the person at the front. Once they have reached the front of the line, the child then has to shout next, so the person at the back knows when to start. Slow but surely the line starts to move forward!

Here's a tip: make the children stand really close together as its a little easier.

The first team to the opposite end of the hall is the winner.