Hello phillean,
Welcome. I think you're on the right track with the 7 x 50 binoculars. They will have great light grasping capacity, provide a wider field of view than higher power ones & also be easier to hold still because of the lower power (as well as probably being less weight to support). You're hand movement will be less exaggerated. Also, it should be easier for the kids to use. It would be good to consider getting fully coated optics to reduce loss from reflection and make sure that they DON'T have rubicon (reddish) coating to reduce glare. This is great for the day time but NOT for astronomy as it will reduce the brightness of objects at night. A final point to consider is being able to attach the binoculars to a simple tripod. They need to have a small screw hole at the front to do this if you want that.
Well all the best and have fun.
