1. Your baby is now starting to understand how things fit together, and their level of spatial awareness is growing. Try offering a palmer grasp cylinder and demonstrate how the cylinder is taken out and put back it before offering your baby a turn. They may also like to try the egg and cup.
2. The sensitive period for language starts at birth, and is very active during your baby's entire first year. It's a good reminder to you when showing your baby a new activity, or trying to demonstrate a new skill, that they are very tuned in to your voice, and will be automatically drawn to watching your mouth move when you speak. Try to "show" things without speaking at first, allowing them to focus on your hands. Once they start to copy your movements, bring the language component in.
3. The pincer grasp is just beginning. Your baby will be very attracted to knobbed puzzles which will meet the need for 'fitting things together' and the pincer grasp practice. Try offering puzzles with only one shape to start with. A circle is the easiest shape to start with as there are no sides to fit into the frame, so your baby doesn't have to hold it the right way. You can also offer a single knobbed cylinder, which has a slightly smaller knob than the puzzle. And of course, lots of finger foods will also develop this skill.
4. Your baby is starting to understand the concept of object permanence. They are realising that an object still exists even if they can't see it. This period also heralds the beginning of their conscious short term memory and working memory development - both very necessary for independent work. You can offer an object permanence box to help them in internalising this understanding.
5. Your baby is very interested in tactile experiences - but they are not yet ready to feel things without seeing them (which requires the ability to visualise something abstractly - a skill that needs the foundation of object permanence and a more developed long term memory). They might enjoy using this very clever mystery box, which has a clear side which allows them to see what they are touching, and can later be turned over to hide the object from view. In the same vein, this see through music box offers an auditory experience with a visual link to what they are hearing.
See here for the first post in this series