Pollinators provide an outstanding framework that can be used to explore many core classroom subjects, including ecology, physiology, behavior, mathematical modeling and evolution. Pollinators are ubiquitous and can be found in almost any rural, suburban or urban landscape. This makes the study of their behaviors and nutritional needs fully accessible, regardless of where you live or go to school.

Please explore the resources for K-12 educators, below, to learn how to incorporate pollinator ecology in the classroom or online via remote instruction. These resources were curated and developed through an ongoing partnership between the Penn State Center for Pollinator Research and Center for Science and the Schools.

Who are the insect pollinators?

Pennsylvania is home to many important pollinating insects including butterflies, bees, flies and even some beetles! There is a tremendous diversity of pollinating insects out there that provides an opportunity for discovery and exploration. Some pollinators specialize on just one or two flowering plant species, with others who will happily forage on more than 50 different plant species, depending on what is available. Below are some resources that can be integrated into lesson plans for students to capture, describe, identify, and learn about different pollinating insects that you may come across in your local landscape.

A common scientific method used to catalog pollinators involves trapping them in liquid-filled cups known as 'bee bowls'. This is a relatively inexpensive and effortless technique that any budding entomologist can experiment with. If you want to sample bees using bee bowls, Sam Droege (USGS) has recorded a video tutorial on this: Surveying Bees Using Bee Bowls (Part One) and Surveying Bees Using Bowls (Part Two).

The Handy Bee Manual provides a comprehensive guide to sampling pollinators, identifying them, and storing them. This guide, along with additional information, can be found on the USGS Native Bee Inventory and Monitoring site.

The guide Identifying & Observing Pollinating Insects in Pennsylvania can help your students identify the main bee species in Pennsylvania landscapes. This and other complementary resources, including a full checklist of all known bee species in Pennsylvania, can be found on the López-Uribe Lab website.

The Seek app from iNaturalist can help you identify plant and pollinator species using machine learning algorithms, with occasional confirmation from trained, naturalist volunteers. This is an easy and fun way to learn more about the composition of insect and plant communities in your area and contribute to a growing database of when and where different species are found across the country. It can be found on the Apple Store (Apple devices) and Google Play Store (Samsung and Google devices).

Which plants are most attractive to pollinators?

Pollinators and plants represent one of the most important mutualisms on our planet. Nearly 90% of flowering plants use pollinators to move pollen among flowers and individual plants, allowing them to set seed and fruit. Pollinators obtain nectar and pollen from plants, which provides them with carbohydrates (nectar) and proteins and lipids (pollen). Plants have evolved to attract different kinds of pollinators (bees, flies, butterflies, hummingbirds, bats) by expressing different visual and olfactory traits, like flower shape, size, color and smell (i.e., flowers that attract bees are typically sweet-smelling, flowers that attract flies are typically not). These are called “pollination syndromes". However, some pollinators can learn to visit other types of flowers, particularly if there are not many flowering plant species available. Recent scientific papers discussing pollination syndromes include a review from Junker and Parachnowitch 2015 and Kantsa et al 2018.

You can compare the types and numbers of pollinators attracted to flowering plants on your school grounds, and explore with your class the diversity of pollinators, the diversity of plants, and the traits of both plants and pollinators that coordinate these mutualistic interactions. Get started by downloading the classroom guide: Plant-Pollinator Interactions.

Alternatively, consider exploring the evolution of pollinator syndromes using the following guide and background information:

Pollinator Syndromes
Entomology/Pollination Syndromes for Master Naturalists - Fall 2020

Refer to the Michigan State University PDF, Smart Gardening: Know the insects that look like bees, and this CPR visual guide to help participants recognize and ID insects that are visiting flowers

Another way to explore the nutritional needs of pollinators involves collecting pollen off of foraging bees in the landscape, and matching the pollen on their bodies to the pollen from different, nearby flowers using microscopy and pollen staining techniques. This project can reveal the different diets that are required of different types of insect pollinators. It can also reveal which flowering plant species might be the most popular with wild pollinator species in your community, which may guide future planting decisions. This provides an excellent opportunity to develop skills in creating collections, databasing, taxonomy, and microscopy. Start exploring the nutritional needs of pollinators by downloading the lesson plan: Pollen Microscopy to Reveal Pollinator Diet Breadth.

(Please note that the pollen microscopy lesson requires access to a microscope to see the different shapes and sizes of pollen grains. If you don't have access to a microscope in your classroom, they can be obtained affordably through various third party vendors, such as the Foldscope, for as little as $1.75 each when bought in bulk.)

Macro image of Pollen

These pollen grains were collected from bees in an almond orchard and stained with fuchsin jelly (100X magnification). The shape, size and appearance of pollen grains vary widely and can teach us about the dietary needs of different bee species.

Is my habitat good for pollinators?

Use this guide and habitat assessment to see if your yard, garden, school grounds, etc., provides a good habitat for bees:

Will the bees like it here? Measuring habitat quality for wild pollinators

Will the bees like it here habitat assessment

Even if you do not have a pollinator garden in your school, you can lead your class in a habitat assessment to explore the resources available to pollinators coupled with a survey of the diversity of pollinator species.

Another way to assess habitat quality across different landscapes is by visiting the Beescape website. Through this website, you can explore the land use patterns and landscape quality for pollinators throughout the domestic U.S.

Additionally, consider signing up to become a 'Dandelion Detective' through a pollination community science program led by The Ohio State University. In this program, you will have an opportunity to contribute data about the flowering plants that support insects in local greenspaces.

How do we assess plants for pollinator nutritional quality?

The amount and nutritional quality of both nectar and pollen can vary between different plant species, and on the growing conditions of the plant. For example, cucumber plants grown in vermicompost soil produce more pollen with more protein and are more attractive to bumble bees than plants grown in soil with chemical fertilizers (see Cardoza et al 2012). Additionally, protein content of goldenrod pollen decreases as atmospheric carbon dioxide levels increase (see Ziska 2016), and nectar content of a flowering perennial decreases with increasing temperature (Mu et al 2015).

Protocols for evaluating the protein, carbohydrate and lipid (fat) quantities of pollen can be found in Vaudo et al 2020. The amount of sugar in a sample of nectar can be measured using a hand-held refractometer. Nectar can be sampled and quantified using a microcapillary tube.

Pollen or nectar and nectar can be collected directly from flowering plants in your area. You can also purchase single-source pollen from commercial distributors, or partner with a local beekeeper to obtain honey bee-collected pollen. Pollen traps placed on the entrance of honey bee colonies will dislodge the pollen balls from the honey bees' pollen baskets, and the resulting “pollen balls" can be sorted by color, which roughly corresponds to the different floral species (see Conti et al 2016).

Other educational materials

Virus transfer through plant-pollinator foraging networks. Bees can be infected with many different viruses, some of which we know are detrimental to honey bee health. Viruses can be transmitted across many bee species in cases when an infected bee visits a flower, and then other bees subsequently visit the same flower. When honey bees return to the colony with virus-contaminated pollen or nectar, it can be fed to other bees and developing larvae in the colony. Modeling Pollen-Mediated Virus Spread in Bee Colonies as a Classroom Activity describes a classroom activity to model the transfer of viruses from flowers to honey bee colonies.

Pollen experiment

Matching pollen grains to flowering plants and their insect visitors. Plants that have evolved to rely on insect-mediated pollination take on physical features that make them more attractive to pollinators, with pollen grains specially evolved to stick to the hairs that are found all over the bodies of different insect species. Use the 3-D pollen grain models available from the 3D Pollen Project to discuss pollination syndromes that may have guided the evolution of distinct flower and pollen grain morphologies to better suit their pollinators.