Approximations will work fine. Don't let the lack of equiptment delay your science projects. Often you will need a certain number of grams of a substance. I plan to weigh several common substances so you can easily mix media with acceptable precision. I used a staight edge such as a knife to strike off the excess so that I had exactly level spoonsfull.
Cooks work the same way.
The call these level spoonsfull. I will do the same for table salt, corn starch, water, and other foods. Useful Salvage Volumetric Tools. Find two 500 ml pop bottles. Fill one to the neck with water.