I recently purchased a kids' chemistry set, mainly because my second-grader expressed an interest and seemed genuinely and reassuringly concerned about the possibility of blowing anything up.

Now, I realize that I should have been prepared for how such a set would work, but I was initially disappointed because each time my sons and I began to follow the directions, it occurred to me that we had no idea why we were mixing one thing with another, no guiding goal other than to find out what the makers of the set thought we should see. We had no question, and certainly no hypothesis. It felt a little aimless.

Of course, it was fun to see the solution turn blue or get fizzy or whatnot, and afterward, before we read the provided explanation, we would think about why we'd gotten that particular result. Once, our solution turned blue when it wasn't supposed to, and we figured out that we hadn't sufficiently cleaned our test tube at the conclusion of our previous experiment.

Overall, though, I was realizing that these were not really experiments but recipes, precise sets of directions to get a predetermined result. I recalled a chart in the introduction to Picture Perfect Science Lessons, an excellent teaching resource that shows how to enhance science education with picture books. In the chart, authors Karen Ansberry and Emily Morgan present a continuum of teacher guidance, from complete direction of dependent students to loose oversight of self-directed learners. The activities provided with our chemistry set definitely fall on the "completely teacher-guided" end of this continuum, which means that they score pretty low in their ability to teach kids about scientific inquiry.

Here's what changed my mind about the value of performing these types of completely guided activities: on more than one occasion, performing the guided activity sparked an interest in further research and exploration. The real fun and learning started after the initial experiment was over.

For example, most recently, we created a pigment called Prussian blue by mixing potassium hexacyanoferrate(II) with a solution of water and ammonium iron(III) sulfate. The explanation of the reaction in the instruction booklet was cursory, so we went online to find out a little more about what was going on. In the process, we discovered that Prussian blue is historically significant; discovered in the early 1700s, it is considered the first modern synthetic pigment and was hugely commercially successful at a time when the only other blue available to European artists was an expensive import from Afghanistan.

It turns out that it's also medicinally valuable—for example, in pathology tests for bone marrow and as an antidote to cesium and thallium poisoning. Furthermore, its discovery was the result of a mistake.

After this history lesson, my sons decided they wanted to turn the Prussian blue we'd created into something they could paint with. The problem was that, at the moment, our pigment was a precipitate at the bottom of a liquid. In a move somewhat at odds with my advice last month, we researched how to extract our pigment from the liquid, but unfortunately we didn't have much success with filtering (we ended up with blue coffee filters and a lot of pigment still in the liquid solution; perhaps coffee filters were not the proper choice).

One of my sons suggested letting the liquid evaporate instead, so I now have a small jar of bluish liquid sitting on a shelf. It's been a few days now, and the liquid is almost gone. We're hopeful that what will be left behind will be a nice blue powder.

We can't paint with a powder, though. We researched turning pigments into paint and discovered that we need a binder, such as linseed oil. The linseed oil we have for polishing furniture is brownish orange, so we'll need to look into whether other oils would work or acquire clear linseed oil.

In short, we're still experimenting.

It was only after I'd seen this transformation from completely guided activity to student-directed inquiry and experimentation that I understood why the continuum I'd seen in Picture Perfect Science Lessons was not labeled with "good" and "bad" ends. In fact, the authors argue that, contrary to common misperception, it is neither possible nor practical to teach all science through inquiry. For example, teaching lab safety through inquiry might have undesirable outcomes.

Thus, I've learned that good science education involves a variety of activities with differing degrees of teacher involvement and direction. And when I think about the similarity between the directions in our chemistry set's instruction booklet and the recipes in any of my many cookbooks, I remember how I used to follow recipes down to the smallest detail. I once even included the olives in a dish I was serving to company even though I knew that none of the diners, including me, liked olives. Today I'm a lot bolder and frequently cook without a recipe at all, sometimes with wild foods I can't find in recipes anyway.

But I'm not throwing the recipes out, and I think I'll keep the chemistry set, too.