Sensory activity ideas

My little one is 5 months old today! He’s a chilled little guy and would happily play on his playmat or recently his jumperoo but is getting frustrated with not being able to move yet 🙈 so I’m looking for some sensory activities little ones actually enjoy? He liked the water for about 30 seconds and hated the peas at the moment 😅 he is poorly so I’m guessing that makes a difference!