Designed to help students understand the DNA double helix. I created this model when I could not locate a model which produced a reasonable helical shape without the students understanding the shape they were trying to achieve in advance. Two variants are provided; a relatively simple one, suitable for most uses, which has the bases already paired and a slightly more complex one which requires students to match the complementary bases as they construct the model. The second is a little more time consuming but may be useful for helping students comprehend the formation of the double helix. Once complete, individual students may join their models to represent a chromosome.

Allows teachers to customise a Periodic Table by selecting what information is to be included in the table. Three versions of the Periodic Table are available; a basic version suitable for younger students and two which present more information. Customisation is achieved by pulldown menus, selecting from a list of elemental properties including atomic mass, date of discovery, melting point, boiling point, electronic configuration, electronegativity, first ionisation energy, density and crustal abundance. The workbook is unprotected to allow you to modify any Periodic Table to suit your own requirements, so keeping a backup copy is recommended.