> safe objects, heavy cardboard or plush books with simple colorful pictures I'm not sure if you're joking or just don't have any kids yourself, but those are

> safe objects, heavy cardboard or plush books with simple colorful pictures I'm not sure if you're joking or just don't have any kids yourself, but those are more age-appropriate for a 3-month-old than a 3-year-old. 3-year-olds generally can make art independently, turn paper pages carefully, pretend and role play, draw by holding pens with their fingers, speak 300-500 words in sentences of six or more words, tell stories, climb, ride tricycles (maybe a scooter!), use safety scissors, and so on. 3-year-olds are far beyond the goo goo gaa gaa phase of life. Simple STEM toys (like what OP is looking for) are totally appropriate for most 3-year-olds. Sure, you're not going to explain tensor physics to them but you can certainly build a bridge with Duplo blocks with them and experiment with different ways of making it strong. You can read more about basic development milestones here: https://www.cdc.gov/ncbddd/actearly/milestones/milestones-3yr.html https://www.cdc.gov/ncbddd/actearly/milestones/milestones-3y...