I visited the Grand Canyon in August 2016. I stayed 2 nights in Tusoyan town (just 5 minutes from the park). I did two day trips.

1) like Els above, walked to Hermit and drove along the other view points.

2) the South Kaibab Trail hike up to Skeleton Point. This is a hike you really should do. it's betweeen 4-6 hours pending how fast you go. I walked with my daughter of 11 and she could easily do it. Don't take your grandma there!

Make sure to take water. A LOT. At least 5 liter per person I think.

check my site for Panorama photos. some made of 80 separate photos making them 150 MP resolution (the original; the one on the site are downsized.) If you are interested in the 150 MP resolution files ask me!