ANOTHER GAME TO PLAY WITH THE HERD- Ball Toss. Would also make a great "rainy day" activity. You could even find tubs or buckets of varying sizes (like nesting bins) for more of a challenge for the older kids (Think Skee-ball).
Diy Cardboard Slide ~When I was a kid, we did this! ***One improvement: make the cardboard about a foot narrower than the stair width, so that there is space for the kids to climb up on the stairs rather than the cardboard slide.