LAKE COUNTY, Calif. — The Lake County Museum is planning a “STEM Days” series at the Courthouse Museum and Gibson Museum this fall.

The free events will explore how science and history intersect.

Topics will include surface tension, oxidation, oxygen, borax, borax, emulsion and casein plastic.

The schedule for the drop-in STEM Days series, from noon to 2 p.m. on each of the dates — with the exception of a full day at the Dickens Fair — follows.

Courthouse Museum: 255 N. Main St., Lakeport

Saturday, Sept. 7: Surface tension — make giant bubbles and learn how surface tension helps fight fires.

Saturday, Sept. 21: Oxygen — make some elephant toothpaste and learn how oxygen effects items in the Museum Collection.

Saturday, Oct. 5: Borax — make and take home slime and learn about Lake County’s borax mines.

Saturday, Oct. 19: Oxidation — learn how this process affected Lake County pear farmers and what turns fruit brown.

Saturday, Nov. 2: Emulsion — learn more about this process and make your own butter.

Saturday, Nov. 23, Dickens Fair Booth, all day: Casein plastic — decorate an ornament out of this plastic that is made from milk.

Gibson Museum: 21267 Calistoga Road, Middletown

Saturday, Sept. 14: Surface tension — make giant bubbles and learn how surface tension helps fight fires.

Saturday, Sept. 28: Oxygen — make some elephant toothpaste and learn how oxygen effects items in the Museum Collection.

Saturday, Oct. 12: Borax — make and take home slime and learn about Lake County’s borax mines.

Saturday, Oct. 26: Oxidation — learn how this process affected Lake County pear farmers and what turns fruit brown.

Saturday, Nov. 16: Emulsion — learn more about this process and make your own butter.

Friday, Dec. 6: Casein plastic — decorate an ornament out of this plastic that is made from milk.