In reply to reo:
It's probably worth having a look at the Plasir west guide - it covers most of those areas (although mostly multi pitch routes) Do you have a car? If so the following are all probably places you can combine with your visit to Grindlewald.
I used to live in Kandersteg - so all are based on living there!
Stockhorn - Stockhorn, mostly well bolted single pitch limestone. Quite sharp but some fun water fluting type features. Recommended mostly for the view (above Thunersee with Eiger, Monch, Jungfrau beyond) and unique location/approach- on the summit block of Stockhorn 5 mins walk from cafe/cable car station.
Bockstor#photos - Bockstor - nice crag short distance from Interlaken. Nice rock in the trees, but nice views from the top. Short and well bolted. This and Neuhaus nearby saved many a rainy day higher up in the mountains - lot dryer down there than up at Grindlewald.
Gletscherschult as mentioned above is good for an afternoon - especially if you're based in Grindlewald without a car. If I remember right, you can catch a bus right to the crag (was free with the village guest card). Not as nice as the other 2 - views aren't as good and a bit polished if I remember right.
Lots of options for easy multi pitch routes.
Familienroute (5c) Might be the best easy one. Great rock, well equipped (can bail from any pitch) and hardest pitches are short and have an easier variation. Not super convenient from Grindlewald you will probably pass through Kandersteg on the way from Saas to Grindlewald.
Also look at Hintisberg amazing crag above Grindlewald - multi pitch routes from F5c. I also heard good stuff about the routes on Jegihorn above Saas Grund for long easy multi pitch. But not done them.
Hope that helps!