Dealing with a puppy with a slight leg sprain

My 10 week old pup over-extended herself the other day, and has been limping a little on her back leg. It is improving rapidly (it happened yesterday afternoon, and the limping is already pretty much gone, except when she gets up from sleeping or after a pee, when she is either stiff, or tensing the sore muscle) so I am not worried about it, but wanted a little advice on keeping her happy while she is sore.

She has been very, very bored and over excited today - she isn't going up and down stairs, because it is sore, and she hasn't been able to go for long walks as usual, for the same reason - she gets sore. Because of that, she is not getting the usual amount of exercise, so she isn't the sleepy, relaxed pup I am used to! Any ideas on how to tire her out and get her exercise without lots of walking?

I'm sure she'll be fine in a day or so, but I don't want her to be going mad barking with boredom in the meantime, and I can't walk her like I usually do...