Our boys love their clam shell. It used to have sand but I got sick of vacuuming it off the floor. I'll restock it over winter but for now with the hot weather we use it for water play. On a hot day I half fill 2 buckets with water and put them in the clam shell with a few plastic cups and empty bottles and the boys have a blast measuring the water and moving it around between the buckets and containers. When they've finished we put it on the gardens so they carry it around pouring it on plants.
They also love their balls.
We also have a play-gym with a slide that they like.
The hopper gets used occasionally but they get bored and forget it then re-discover it again.
Also they have one of those 'trikes' that are foot powered not pedal powered and they love it.