A really fun activity I got the kids I tutor to do is 1, print off a science experiment template off twinkl or basically list experiment name/equipment/what I did/what happened and get them to think of a question and answer it through trying it out, and writing down their findings in that format. 8yo tried to find out which type of surface out of a few (paper, card, fabric etc) can be wiped down the easiest with paint on, and the 6yo mixed paint with water and tried to see what would absorb it fastest, paper, tissue or fabric scraps etc. Used the same stuff for both kids, and other experiments for older kids can be mixing kitchen stuff like baking soda and lemon with water or the litmus test with washing up powder as the alkaline and lemon as the acid and red cabbage as the universal indicator. Making them write it up as well will drag things out and its educational and fun
Also older kids can be prompted to write a hypothesis before they start