We just got back from a week at the cape and stayed in South Yarmouth. We were on South Shore drive and had access to the 4 beaches that line the strip.
The beach right in front of our cottage was Seaview beach. The sand is super soft and clean, the water has small waves and it is on the warmer side.
The wind was terrible (not sure if it was just the week we happened to be there)! It was very hard for the kids to play in the sand because it was so windy. Also the beaches are small and everyone is literally on top of each other. Two days in a row there was a pile of poop at the entrance going down to the beach. It was in 2 different spots on the top steps and we suspect it was human. So gross.
Other than that the beaches are clean and the restrooms are clean. The small playground is good for the kids (mostly swings). The water is not clear and you get rocks and seaweed at certain times (didn't bother us). We never swam in it because we prefer calmer water.
We ended up driving to Mayflower beach and spent the days there, this year Mayflower was on the cold side as for water temp but in the past it was warmer.
The Skipper restaurant across the street from playground has great food and an ice cream stand.
Don't buy from the ice cream truck that drives thru every hr, the ice cream and Popsicles are so expensive on it!
All and all we enjoyed south yarmouth and the tons of food options and kid stuff on rt 28 but we would not stay here again because of the beaches. We definitely prefer the bay side and it's hard to beat Mayflower!
Glad we tried it and we had a great vacation