It's fine to help your kids with their science projects, but that doesn't mean doing it for them.
Mom cut herself with a pair of scissors while cutting a twig so the 12 year old wouldn't. Why she needed to use the scissors in the first place was beyond me since the project entailed creating a primitive tool. I don't think primitive people used scissors to fashion tools.
As she received 5 sutures mom commented: "We better get an A on this project".
WTF? I never got a lot of help on my projects from my parents except to cart it to and from school. Unless it involved power tools, then I wasn't allowed to use the chain saw. Lame Styrofoam solar systems or exploding volcanoes were otherwise my responsibility.
Once I had to do a working digestive system. I traced my little brother's outline on a piece of plywood, then filled in the esophagus, stomach, intestines etcetera. My dad drew a profile (face only) of Lucy (Peanuts Lucy, not I Love Lucy...although THAT would have been interesting). My little brother was upset that I put Lucy on his body but he got over it. I got some plastic tubing that I stapled gingerly on the plywood being careful not to poke holes in it. Thus I was able to demonstrate the fascinating journey of food, using Kool-Aid, through the body from start to finish. Everyone thought it was gross, but that's fourth grade for you. I got an A on the project. "We" didn't get an A.